Redirect old API V3 page and update links

doc/api/api_resources.md

@@ -14,7 +14,6 @@ Available resources for the [GitLab REST API](index.md) can be grouped in the fo
 
 See also:
 
-- [V3 to V4](v3_to_v4.md).
 - Adding [deploy keys for multiple projects](deploy_keys.md#add-deploy-keys-to-multiple-projects).
 - [API Resources for various templates](#templates-api-resources).
 

doc/api/index.md

@@ -62,7 +62,7 @@ month. Major API version changes, and removal of entire API versions, are done i
 with major GitLab releases.
 
 All deprecations and changes between versions are in the documentation.
-For the changes between v3 and v4, see the [v3 to v4 documentation](v3_to_v4.md).
+For the changes between v3 and v4, see the [v3 to v4 documentation](https://gitlab.com/gitlab-org/gitlab-foss/-/blob/11-0-stable/doc/api/v3_to_v4.md).
 
 ### Current status
 

doc/api/v3_to_v4.md

 ---
-stage: Ecosystem
-group: Integrations
-info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments
+redirect_to: 'https://gitlab.com/gitlab-org/gitlab-foss/-/blob/11-0-stable/doc/api/v3_to_v4.md'
+remove_date: '2023-01-31'
 ---
 
-# API V3 to API V4
+This document was moved to [another location](https://gitlab.com/gitlab-org/gitlab-foss/-/blob/11-0-stable/doc/api/v3_to_v4.md).
 
-WARNING:
-The GitLab API v3 was [removed](https://gitlab.com/gitlab-org/gitlab-foss/-/issues/36819) in GitLab 11.0.
-
-For information about the current version of the GitLab API, read the [API documentation](index.md).
-
-## Related topics
-
-- [GitLab v3 API documentation](https://gitlab.com/gitlab-org/gitlab-foss/-/blob/8-16-stable/doc/api/index.md)
-- [Migration guide](https://gitlab.com/gitlab-org/gitlab-foss/-/blob/11-0-stable/doc/api/v3_to_v4.md) from
-  v3 to v4
+<!-- This redirect file can be deleted after <2023-01-31>. -->
+<!-- Before deletion, see: https://docs.gitlab.com/ee/development/documentation/#move-or-rename-a-page -->