Merge branch '478861-introduce-merge-check-for-policy-violations' into 'master'

Resolve "Introduce merge check for policy violations"

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/166300



Merged-by: Sashi Kumar Kumaresan <skumar@gitlab.com>
Approved-by: Martin Čavoj <mcavoj@gitlab.com>
Approved-by: Sashi Kumar Kumaresan <skumar@gitlab.com>
Reviewed-by: Sashi Kumar Kumaresan <skumar@gitlab.com>
Reviewed-by: Artur Fedorov <afedorov@gitlab.com>
Reviewed-by: Martin Čavoj <mcavoj@gitlab.com>
Co-authored-by: Marc Shaw <mshaw@gitlab.com>