Merge branch '510191-disable-role-delete-button' into 'master'

Block custom role from deletion if there are dependent policies

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/176340



Merged-by: Gregory Havenga <11164960-ghavenga@users.noreply.gitlab.com>
Approved-by: Dominic Bauer <dbauer@gitlab.com>
Approved-by: Alper Akgun <aakgun@gitlab.com>
Approved-by: Gregory Havenga <11164960-ghavenga@users.noreply.gitlab.com>
Approved-by: mo khan <mo@mokhan.ca>
Reviewed-by: Alper Akgun <aakgun@gitlab.com>
Reviewed-by: Alexander Turinske <aturinske@gitlab.com>
Reviewed-by: Dominic Bauer <dbauer@gitlab.com>
Reviewed-by: mo khan <mo@mokhan.ca>
Co-authored-by: Sashi Kumar Kumaresan <skumar@gitlab.com>
Co-authored-by: Alexander Turinske <aturinske@gitlab.com>