Improve cross-linking for push options

We don't talk about push options as frequently as we should. Let's
start by building in a few cross-links.

doc/administration/server_hooks.md

@@ -15,7 +15,7 @@ Server hooks run custom logic on the GitLab server. Users can use them to run Gi
 - Enforcing specific commit policies.
 - Performing tasks based on the state of the repository.
 
-Server hooks use `pre-receive`, `post-receive`, and `update` 
+Server hooks use `pre-receive`, `post-receive`, and `update`
 [Git server-side hooks](https://git-scm.com/book/en/v2/Customizing-Git-Git-Hooks#_server_side_hooks).
 
 GitLab administrators configure server hooks on the file system of the GitLab server. If you don't have file system access,
@@ -124,8 +124,8 @@ The following Git environment variables are supported for `pre-receive` and `pos
 |:-----------------------------------|:-----------------------------------------------------------------------------------------------------------------------------------------------------------------------|
 | `GIT_ALTERNATE_OBJECT_DIRECTORIES` | Alternate object directories in the quarantine environment. See [Git `receive-pack` documentation](https://git-scm.com/docs/git-receive-pack#_quarantine_environment). |
 | `GIT_OBJECT_DIRECTORY`             | GitLab project path in the quarantine environment. See [Git `receive-pack` documentation](https://git-scm.com/docs/git-receive-pack#_quarantine_environment).          |
-| `GIT_PUSH_OPTION_COUNT`            | Number of push options. See [Git `pre-receive` documentation](https://git-scm.com/docs/githooks#pre-receive).                                                          |
-| `GIT_PUSH_OPTION_<i>`              | Value of push options where `i` is from `0` to `GIT_PUSH_OPTION_COUNT - 1`. See [Git `pre-receive` documentation](https://git-scm.com/docs/githooks#pre-receive).      |
+| `GIT_PUSH_OPTION_COUNT`            | Number of [push options](../user/project/push_options.md). See [Git `pre-receive` documentation](https://git-scm.com/docs/githooks#pre-receive).                                                          |
+| `GIT_PUSH_OPTION_<i>`              | Value of [push options](../user/project/push_options.md) where `i` is from `0` to `GIT_PUSH_OPTION_COUNT - 1`. See [Git `pre-receive` documentation](https://git-scm.com/docs/githooks#pre-receive).      |
 
 ## Custom error messages
 

doc/install/installation.md

@@ -567,6 +567,7 @@ sudo -u git -H git config --global gc.auto 0
 sudo -u git -H git config --global repack.writeBitmaps true
 
 # Enable push options
+# Refer to https://docs.gitlab.com/ee/user/project/push_options.html for more information.
 sudo -u git -H git config --global receive.advertisePushOptions true
 
 # Enable fsyncObjectFiles to reduce risk of repository corruption if the server crashes
@@ -1143,7 +1144,7 @@ You can configure the Prometheus server in `config/gitlab.yml`:
 # example
 prometheus:
   enabled: true
-  server_address: '10.1.2.3:9090' 
+  server_address: '10.1.2.3:9090'
 ```
 
 ## Troubleshooting

doc/user/project/merge_requests/index.md

@@ -137,3 +137,4 @@ For a web developer writing a webpage for your company's website:
 - [Suggest code changes](reviews/suggestions.md)
 - [Commits](commits.md)
 - [CI/CD pipelines](../../../ci/index.md)
+- [Push options](../push_options.md) for merge requests