This introduces a new flag `BlockAdminMergeOverride` on the branch
protection rules that prevents admins/repo owners from bypassing branch
protection rules and merging without approvals or failing status checks.
Fixes#17131
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Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
Co-authored-by: Giteabot <teabot@gitea.io>
