Merge branch 'docs-squash-ff' into 'master'

Update feature flag status for squash commit options

See merge request gitlab-org/gitlab!39516

doc/user/project/merge_requests/squash_and_merge.md

@@ -92,7 +92,7 @@ squashing can itself be considered equivalent to rebasing.
 ## Squash Commits Options
 
 > - [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/17613) in GitLab 13.2.
-> - It's deployed behind a feature flag, enabled by default.
+> - It's deployed behind a feature flag, enabled by default in GitLab 13.3.
 > - It's enabled on GitLab.com.
 > - It's recommended for production use.
 > - For GitLab self-managed instances, GitLab administrator can opt to [disable it](#enable-or-disable-squash-commit-options-core-only). **(CORE ONLY)**