Update API code blocks to use 'plaintext'

The code blocks for each API call on these pages did not specify a
code style. While these are HTTP requests (GET, POST, DELETE, PUT,
etc.) they aren't structured in the way the 'http' lexer expects.
I chose 'plaintext' instead of 'http' for better legibility.

doc/api/appearance.md

@@ -9,7 +9,7 @@ Appearance API allows you to maintain GitLab's appearance as if using the GitLab
 
 List the current appearance configuration of the GitLab instance.
 
-```
+```plaintext
 GET /application/appearance
 ```
 
@@ -39,7 +39,7 @@ Example response:
 
 Use an API call to modify GitLab instance appearance configuration.
 
-```
+```plaintext
 PUT /application/appearance
 ```
 

doc/api/audit_events.md

@@ -8,7 +8,7 @@ To retrieve audit events using the API, you must [authenticate yourself](README.
 
 ### Retrieve all instance audit events
 
-```
+```plaintext
 GET /audit_events
 ```
 
@@ -87,7 +87,7 @@ Example response:
 
 ### Retrieve single instance audit event
 
-```
+```plaintext
 GET /audit_events/:id
 ```
 
@@ -126,7 +126,7 @@ To retrieve group audit events using the API, you must [authenticate yourself](R
 
 ### Retrieve all group audit events
 
-```
+```plaintext
 GET /groups/:id/audit_events
 ```
 
@@ -188,7 +188,7 @@ Example response:
 
 Only available to group owners and administrators.
 
-```
+```plaintext
 GET /groups/:id/audit_events/:audit_event_id
 ```
 

doc/api/boards.md

@@ -9,7 +9,7 @@ request on that project will result to a `404` status code.
 
 Lists Issue Boards in the given project.
 
-```
+```plaintext
 GET /projects/:id/boards
 ```
 
@@ -83,7 +83,7 @@ Example response:
 
 Get a single board.
 
-```
+```plaintext
 GET /projects/:id/boards/:board_id
 ```
 
@@ -157,7 +157,7 @@ Example response:
 
 Creates a board.
 
-```
+```plaintext
 POST /projects/:id/boards
 ```
 
@@ -233,7 +233,7 @@ Example response:
 
 Updates a board.
 
-```
+```plaintext
 PUT /projects/:id/boards/:board_id
 ```
 
@@ -312,7 +312,7 @@ Example response:
 
 Deletes a board.
 
-```
+```plaintext
 DELETE /projects/:id/boards/:board_id
 ```
 
@@ -330,7 +330,7 @@ curl --request DELETE --header "PRIVATE-TOKEN: <your_access_token>" https://gitl
 Get a list of the board's lists.
 Does not include `open` and `closed` lists
 
-```
+```plaintext
 GET /projects/:id/boards/:board_id/lists
 ```
 
@@ -387,7 +387,7 @@ Example response:
 
 Get a single board list.
 
-```
+```plaintext
 GET /projects/:id/boards/:board_id/lists/:list_id
 ```
 
@@ -421,7 +421,7 @@ Example response:
 
 Creates a new Issue Board list.
 
-```
+```plaintext
 POST /projects/:id/boards/:board_id/lists
 ```
 
@@ -463,7 +463,7 @@ Example response:
 
 Updates an existing Issue Board list. This call is used to change list position.
 
-```
+```plaintext
 PUT /projects/:id/boards/:board_id/lists/:list_id
 ```
 
@@ -498,7 +498,7 @@ Example response:
 
 Only for admins and project owners. Deletes the board list in question.
 
-```
+```plaintext
 DELETE /projects/:id/boards/:board_id/lists/:list_id
 ```
 

doc/api/commits.md

@@ -4,7 +4,7 @@
 
 Get a list of repository commits in a project.
 
-```
+```plaintext
 GET /projects/:id/repository/commits
 ```
 
@@ -67,7 +67,7 @@ Example response:
 
 Create a commit by posting a JSON payload
 
-```
+```plaintext
 POST /projects/:id/repository/commits
 ```
 
@@ -190,7 +190,7 @@ curl --request POST \
 
 Get a specific commit identified by the commit hash or name of a branch or tag.
 
-```
+```plaintext
 GET /projects/:id/repository/commits/:sha
 ```
 
@@ -246,7 +246,7 @@ Example response:
 Get all references (from branches or tags) a commit is pushed to.
 The pagination parameters `page` and `per_page` can be used to restrict the list of references.
 
-```
+```plaintext
 GET /projects/:id/repository/commits/:sha/refs
 ```
 
@@ -280,7 +280,7 @@ Example response:
 
 Cherry picks a commit to a given branch.
 
-```
+```plaintext
 POST /projects/:id/repository/commits/:sha/cherry_pick
 ```
 
@@ -339,7 +339,7 @@ conflict.
 
 Reverts a commit in a given branch.
 
-```
+```plaintext
 POST /projects/:id/repository/commits/:sha/revert
 ```
 
@@ -391,7 +391,7 @@ changeset was empty, likely due to the change having already been reverted.
 
 Get the diff of a commit in a project.
 
-```
+```plaintext
 GET /projects/:id/repository/commits/:sha/diff
 ```
 
@@ -427,7 +427,7 @@ Example response:
 
 Get the comments of a commit in a project.
 
-```
+```plaintext
 GET /projects/:id/repository/commits/:sha/comments
 ```
 
@@ -478,7 +478,7 @@ cases below is valid:
 In any of the above cases, the response of `line`, `line_type` and `path` is
 set to `null`.
 
-```
+```plaintext
 POST /projects/:id/repository/commits/:sha/comments
 ```
 
@@ -524,7 +524,7 @@ Since GitLab 8.1, this is the new commit status API.
 List the statuses of a commit in a project.
 The pagination parameters `page` and `per_page` can be used to restrict the list of references.
 
-```
+```plaintext
 GET /projects/:id/repository/commits/:sha/statuses
 ```
 
@@ -598,7 +598,7 @@ Example response:
 
 Adds or updates a build status of a commit.
 
-```
+```plaintext
 POST /projects/:id/statuses/:sha
 ```
 
@@ -651,7 +651,7 @@ Example response:
 
 Get a list of Merge Requests related to the specified commit.
 
-```
+```plaintext
 GET /projects/:id/repository/commits/:sha/merge_requests
 ```
 
@@ -720,7 +720,7 @@ Example response:
 Get the [GPG signature from a commit](../user/project/repository/gpg_signed_commits/index.md),
 if it is signed. For unsigned commits, it results in a 404 response.
 
-```
+```plaintext
 GET /projects/:id/repository/commits/:sha/signature
 ```
 

doc/api/container_registry.md

@@ -10,7 +10,7 @@ This is the API docs of the [GitLab Container Registry](../user/packages/contain
 
 Get a list of registry repositories in a project.
 
-```
+```plaintext
 GET /projects/:id/registry/repositories
 ```
 
@@ -50,7 +50,7 @@ Example response:
 
 Get a list of registry repositories in a group.
 
-```
+```plaintext
 GET /groups/:id/registry/repositories
 ```
 
@@ -116,7 +116,7 @@ Delete a repository in registry.
 
 This operation is executed asynchronously and might take some time to get executed.
 
-```
+```plaintext
 DELETE /projects/:id/registry/repositories/:repository_id
 ```
 
@@ -135,7 +135,7 @@ curl --request DELETE --header "PRIVATE-TOKEN: <your_access_token>" "https://git
 
 Get a list of tags for given registry repository.
 
-```
+```plaintext
 GET /projects/:id/registry/repositories/:repository_id/tags
 ```
 
@@ -169,7 +169,7 @@ Example response:
 
 Get details of a registry repository tag.
 
-```
+```plaintext
 GET /projects/:id/registry/repositories/:repository_id/tags/:tag_name
 ```
 
@@ -202,7 +202,7 @@ Example response:
 
 Delete a registry repository tag.
 
-```
+```plaintext
 DELETE /projects/:id/registry/repositories/:repository_id/tags/:tag_name
 ```
 
@@ -223,7 +223,7 @@ This action does not delete blobs. In order to delete them and recycle disk spac
 
 Delete registry repository tags in bulk based on given criteria.
 
-```
+```plaintext
 DELETE /projects/:id/registry/repositories/:repository_id/tags
 ```
 

doc/api/custom_attributes.md

@@ -9,7 +9,7 @@ which will be referred to as "resource" in this documentation.
 
 Get all custom attributes on a resource.
 
-```
+```plaintext
 GET /users/:id/custom_attributes
 GET /groups/:id/custom_attributes
 GET /projects/:id/custom_attributes
@@ -42,7 +42,7 @@ Example response:
 
 Get a single custom attribute on a resource.
 
-```
+```plaintext
 GET /users/:id/custom_attributes/:key
 GET /groups/:id/custom_attributes/:key
 GET /projects/:id/custom_attributes/:key
@@ -71,7 +71,7 @@ Example response:
 Set a custom attribute on a resource. The attribute will be updated if it already exists,
 or newly created otherwise.
 
-```
+```plaintext
 PUT /users/:id/custom_attributes/:key
 PUT /groups/:id/custom_attributes/:key
 PUT /projects/:id/custom_attributes/:key
@@ -100,7 +100,7 @@ Example response:
 
 Delete a custom attribute on a resource.
 
-```
+```plaintext
 DELETE /users/:id/custom_attributes/:key
 DELETE /groups/:id/custom_attributes/:key
 DELETE /projects/:id/custom_attributes/:key

doc/api/dependencies.md

@@ -16,7 +16,7 @@ Get a list of project dependencies. This API partially mirroring
 This list can be generated only for [languages and package managers](../user/application_security/dependency_scanning/index.md#supported-languages-and-package-managers)
 supported by Gemnasium.
 
-```
+```plaintext
 GET /projects/:id/dependencies
 GET /projects/:id/dependencies?package_manager=maven
 GET /projects/:id/dependencies?package_manager=yarn,bundler

doc/api/deploy_keys.md

@@ -4,7 +4,7 @@
 
 Get a list of all deploy keys across all projects of the GitLab instance. This endpoint requires admin access.
 
-```
+```plaintext
 GET /deploy_keys
 ```
 
@@ -35,7 +35,7 @@ Example response:
 
 Get a list of a project's deploy keys.
 
-```
+```plaintext
 GET /projects/:id/deploy_keys
 ```
 
@@ -72,7 +72,7 @@ Example response:
 
 Get a single key.
 
-```
+```plaintext
 GET /projects/:id/deploy_keys/:key_id
 ```
 
@@ -106,7 +106,7 @@ Creates a new deploy key for a project.
 If the deploy key already exists in another project, it will be joined to current
 project only if original one is accessible by the same user.
 
-```
+```plaintext
 POST /projects/:id/deploy_keys
 ```
 
@@ -137,7 +137,7 @@ Example response:
 
 Updates a deploy key for a project.
 
-```
+```plaintext
 PUT /projects/:id/deploy_keys/:key_id
 ```
 
@@ -167,7 +167,7 @@ Example response:
 
 Removes a deploy key from the project. If the deploy key is used only for this project, it will be deleted from the system.
 
-```
+```plaintext
 DELETE /projects/:id/deploy_keys/:key_id
 ```
 

doc/api/deployments.md

@@ -4,7 +4,7 @@
 
 Get a list of deployments in a project.
 
-```
+```plaintext
 GET /projects/:id/deployments
 ```
 
@@ -177,7 +177,7 @@ Example of response
 
 ## Get a specific deployment
 
-```
+```plaintext
 GET /projects/:id/deployments/:deployment_id
 ```
 
@@ -265,7 +265,7 @@ Example of response
 
 ## Create a deployment
 
-```
+```plaintext
 POST /projects/:id/deployments
 ```
 
@@ -319,7 +319,7 @@ Example of a response:
 
 ## Updating a deployment
 
-```
+```plaintext
 PUT /projects/:id/deployments/:deployment_id
 ```
 
@@ -366,7 +366,7 @@ Example of a response:
 
 This API retrieves the list of merge requests shipped with a given deployment:
 
-```
+```plaintext
 GET /projects/:id/deployments/:deployment_id/merge_requests
 ```
 

doc/api/discussions.md

@@ -22,7 +22,7 @@ Read more on [pagination](README.md#pagination).
 
 Gets a list of all discussion items for a single issue.
 
-```
+```plaintext
 GET /projects/:id/issues/:issue_iid/discussions
 ```
 
@@ -118,7 +118,7 @@ curl --header "PRIVATE-TOKEN: <your_access_token>" https://gitlab.example.com/ap
 
 Returns a single discussion item for a specific project issue
 
-```
+```plaintext
 GET /projects/:id/issues/:issue_iid/discussions/:discussion_id
 ```
 
@@ -138,7 +138,7 @@ curl --header "PRIVATE-TOKEN: <your_access_token>" https://gitlab.example.com/ap
 
 Creates a new thread to a single project issue. This is similar to creating a note but other comments (replies) can be added to it later.
 
-```
+```plaintext
 POST /projects/:id/issues/:issue_iid/discussions
 ```
 
@@ -162,7 +162,7 @@ Adds a new note to the thread. This can also [create a thread from a single comm
 **WARNING**
 Notes can be added to other items than comments (system notes, etc.) making them threads.
 
-```
+```plaintext
 POST /projects/:id/issues/:issue_iid/discussions/:discussion_id/notes
 ```
 
@@ -185,7 +185,7 @@ curl --request POST --header "PRIVATE-TOKEN: <your_access_token>" https://gitlab
 
 Modify existing thread note of an issue.
 
-```
+```plaintext
 PUT /projects/:id/issues/:issue_iid/discussions/:discussion_id/notes/:note_id
 ```
 
@@ -207,7 +207,7 @@ curl --request PUT --header "PRIVATE-TOKEN: <your_access_token>" https://gitlab.
 
 Deletes an existing thread note of an issue.
 
-```
+```plaintext
 DELETE /projects/:id/issues/:issue_iid/discussions/:discussion_id/notes/:note_id
 ```
 
@@ -230,7 +230,7 @@ curl --request DELETE --header "PRIVATE-TOKEN: <your_access_token>" https://gitl
 
 Gets a list of all discussion items for a single snippet.
 
-```
+```plaintext
 GET /projects/:id/snippets/:snippet_id/discussions
 ```
 
@@ -326,7 +326,7 @@ curl --header "PRIVATE-TOKEN: <your_access_token>" https://gitlab.example.com/ap
 
 Returns a single discussion item for a specific project snippet
 
-```
+```plaintext
 GET /projects/:id/snippets/:snippet_id/discussions/:discussion_id
 ```
 
@@ -347,7 +347,7 @@ curl --request POST --header "PRIVATE-TOKEN: <your_access_token>" https://gitlab
 Creates a new thread to a single project snippet. This is similar to creating
 a note but other comments (replies) can be added to it later.
 
-```
+```plaintext
 POST /projects/:id/snippets/:snippet_id/discussions
 ```
 
@@ -368,7 +368,7 @@ curl --request POST --header "PRIVATE-TOKEN: <your_access_token>" https://gitlab
 
 Adds a new note to the thread.
 
-```
+```plaintext
 POST /projects/:id/snippets/:snippet_id/discussions/:discussion_id/notes
 ```
 
@@ -391,7 +391,7 @@ curl --request POST --header "PRIVATE-TOKEN: <your_access_token>" https://gitlab
 
 Modify existing thread note of a snippet.
 
-```
+```plaintext
 PUT /projects/:id/snippets/:snippet_id/discussions/:discussion_id/notes/:note_id
 ```
 
@@ -413,7 +413,7 @@ curl --request PUT --header "PRIVATE-TOKEN: <your_access_token>" https://gitlab.
 
 Deletes an existing thread note of a snippet.
 
-```
+```plaintext
 DELETE /projects/:id/snippets/:snippet_id/discussions/:discussion_id/notes/:note_id
 ```
 
@@ -436,7 +436,7 @@ curl --request DELETE --header "PRIVATE-TOKEN: <your_access_token>" https://gitl
 
 Gets a list of all discussion items for a single epic.
 
-```
+```plaintext
 GET /groups/:id/epics/:epic_id/discussions
 ```
 
@@ -533,7 +533,7 @@ curl --header "PRIVATE-TOKEN: <your_access_token>" https://gitlab.example.com/ap
 
 Returns a single discussion item for a specific group epic
 
-```
+```plaintext
 GET /groups/:id/epics/:epic_id/discussions/:discussion_id
 ```
 
@@ -554,7 +554,7 @@ curl --request POST --header "PRIVATE-TOKEN: <your_access_token>" https://gitlab
 Creates a new thread to a single group epic. This is similar to creating
 a note but but other comments (replies) can be added to it later.
 
-```
+```plaintext
 POST /groups/:id/epics/:epic_id/discussions
 ```
 
@@ -576,7 +576,7 @@ curl --request POST --header "PRIVATE-TOKEN: <your_access_token>" https://gitlab
 Adds a new note to the thread. This can also
 [create a thread from a single comment](../user/discussions/#start-a-thread-by-replying-to-a-standard-comment).
 
-```
+```plaintext
 POST /groups/:id/epics/:epic_id/discussions/:discussion_id/notes
 ```
 
@@ -599,7 +599,7 @@ curl --request POST --header "PRIVATE-TOKEN: <your_access_token>" https://gitlab
 
 Modify existing thread note of an epic.
 
-```
+```plaintext
 PUT /groups/:id/epics/:epic_id/discussions/:discussion_id/notes/:note_id
 ```
 
@@ -621,7 +621,7 @@ curl --request PUT --header "PRIVATE-TOKEN: <your_access_token>" https://gitlab.
 
 Deletes an existing thread note of an epic.
 
-```
+```plaintext
 DELETE /groups/:id/epics/:epic_id/discussions/:discussion_id/notes/:note_id
 ```
 
@@ -644,7 +644,7 @@ curl --request DELETE --header "PRIVATE-TOKEN: <your_access_token>" https://gitl
 
 Gets a list of all discussion items for a single merge request.
 
-```
+```plaintext
 GET /projects/:id/merge_requests/:merge_request_iid/discussions
 ```
 
@@ -793,7 +793,7 @@ curl --header "PRIVATE-TOKEN: <your_access_token>" https://gitlab.example.com/ap
 
 Returns a single discussion item for a specific project merge request
 
-```
+```plaintext
 GET /projects/:id/merge_requests/:merge_request_iid/discussions/:discussion_id
 ```
 
@@ -814,7 +814,7 @@ curl --header "PRIVATE-TOKEN: <your_access_token>" https://gitlab.example.com/ap
 Creates a new thread to a single project merge request. This is similar to creating
 a note but other comments (replies) can be added to it later.
 
-```
+```plaintext
 POST /projects/:id/merge_requests/:merge_request_iid/discussions
 ```
 
@@ -848,7 +848,7 @@ curl --request POST --header "PRIVATE-TOKEN: <your_access_token>" https://gitlab
 
 Resolve/unresolve whole thread of a merge request.
 
-```
+```plaintext
 PUT /projects/:id/merge_requests/:merge_request_iid/discussions/:discussion_id
 ```
 
@@ -870,7 +870,7 @@ curl --request PUT --header "PRIVATE-TOKEN: <your_access_token>" https://gitlab.
 Adds a new note to the thread. This can also
 [create a thread from a single comment](../user/discussions/#start-a-thread-by-replying-to-a-standard-comment).
 
-```
+```plaintext
 POST /projects/:id/merge_requests/:merge_request_iid/discussions/:discussion_id/notes
 ```
 
@@ -893,7 +893,7 @@ curl --request POST --header "PRIVATE-TOKEN: <your_access_token>" https://gitlab
 
 Modify or resolve an existing thread note of a merge request.
 
-```
+```plaintext
 PUT /projects/:id/merge_requests/:merge_request_iid/discussions/:discussion_id/notes/:note_id
 ```
 
@@ -922,7 +922,7 @@ curl --request PUT --header "PRIVATE-TOKEN: <your_access_token>" https://gitlab.
 
 Deletes an existing thread note of a merge request.
 
-```
+```plaintext
 DELETE /projects/:id/merge_requests/:merge_request_iid/discussions/:discussion_id/notes/:note_id
 ```
 
@@ -945,7 +945,7 @@ curl --request DELETE --header "PRIVATE-TOKEN: <your_access_token>" https://gitl
 
 Gets a list of all discussion items for a single commit.
 
-```
+```plaintext
 GET /projects/:id/commits/:commit_id/discussions
 ```
 
@@ -1086,7 +1086,7 @@ curl --header "PRIVATE-TOKEN: <your_access_token>" https://gitlab.example.com/ap
 
 Returns a single discussion item for a specific project commit
 
-```
+```plaintext
 GET /projects/:id/commits/:commit_id/discussions/:discussion_id
 ```
 
@@ -1107,7 +1107,7 @@ curl --header "PRIVATE-TOKEN: <your_access_token>" https://gitlab.example.com/ap
 Creates a new thread to a single project commit. This is similar to creating
 a note but other comments (replies) can be added to it later.
 
-```
+```plaintext
 POST /projects/:id/commits/:commit_id/discussions
 ```
 
@@ -1141,7 +1141,7 @@ curl --request POST --header "PRIVATE-TOKEN: <your_access_token>" https://gitlab
 
 Adds a new note to the thread.
 
-```
+```plaintext
 POST /projects/:id/commits/:commit_id/discussions/:discussion_id/notes
 ```
 
@@ -1164,7 +1164,7 @@ curl --request POST --header "PRIVATE-TOKEN: <your_access_token>" https://gitlab
 
 Modify or resolve an existing thread note of a commit.
 
-```
+```plaintext
 PUT /projects/:id/commits/:commit_id/discussions/:discussion_id/notes/:note_id
 ```
 
@@ -1192,7 +1192,7 @@ curl --request PUT --header "PRIVATE-TOKEN: <your_access_token>" https://gitlab.
 
 Deletes an existing thread note of a commit.
 
-```
+```plaintext
 DELETE /projects/:id/commits/:commit_id/discussions/:discussion_id/notes/:note_id
 ```