Merge branch '482856-refactor-branches-delete-service-spec' into 'master'

Refactor branches delete service spec

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/167404



Merged-by: Terri Chu <tchu@gitlab.com>
Approved-by: Shreyas Agarwal <sagarwal@gitlab.com>
Approved-by: Terri Chu <tchu@gitlab.com>
Reviewed-by: Shreyas Agarwal <sagarwal@gitlab.com>
Co-authored-by: Andy Soiron <asoiron@gitlab.com>