Fix curl commands in vulnerability exports API

doc/api/vulnerability_exports.md

@@ -37,7 +37,7 @@ POST /security/projects/:id/vulnerability_exports
 | `id`                | integer or string | yes        | The ID or [URL-encoded path](README.md#namespaced-path-encoding) of the project which the authenticated user is a member of |
 
 ```shell
-curl --header POST "PRIVATE-TOKEN: <your_access_token>" "https://gitlab.example.com/api/v4/projects/1/vulnerability_exports"
+curl --request POST --header "PRIVATE-TOKEN: <your_access_token>" "https://gitlab.example.com/api/v4/security/projects/1/vulnerability_exports"
 ```
 
 The created vulnerability export is automatically deleted after 1 hour.
@@ -83,7 +83,7 @@ POST /security/groups/:id/vulnerability_exports
 | `id`                | integer or string | yes        | The ID or [URL-encoded path](README.md#namespaced-path-encoding) of the group which the authenticated user is a member of |
 
 ```shell
-curl --header POST "PRIVATE-TOKEN: <your_access_token>" "https://gitlab.example.com/api/v4/security/groups/1/vulnerability_exports"
+curl --request POST --header "PRIVATE-TOKEN: <your_access_token>" "https://gitlab.example.com/api/v4/security/groups/1/vulnerability_exports"
 ```
 
 The created vulnerability export is automatically deleted after 1 hour.
@@ -116,7 +116,7 @@ POST /security/vulnerability_exports
 ```
 
 ```shell
-curl --header POST "PRIVATE-TOKEN: <your_access_token>" "https://gitlab.example.com/api/v4/security/vulnerability_exports"
+curl --request POST --header "PRIVATE-TOKEN: <your_access_token>" "https://gitlab.example.com/api/v4/security/vulnerability_exports"
 ```
 
 The created vulnerability export is automatically deleted after one hour.