Merge branch 'phikai-request-changes-flag' into 'master'

Docs for blocking request changes enabled on GitLab.com

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/157354



Merged-by: Amy Qualls <aqualls@gitlab.com>
Approved-by: Amy Qualls <aqualls@gitlab.com>
Co-authored-by: Kai Armstrong <karmstrong@gitlab.com>