Resolve#32341
~Depends on #27151~
- [x] It will display a checkbox of deleting the head branch on the pull
request view page when starting an auto-merge task.
- [x] Add permission check before deleting the branch
- [x] Add delete branch comment for those closing pull requests because
of head branch or base branch was deleted.
- [x] Merge `RetargetChildrenOnMerge` and `AddDeletePRBranchComment`
into `service.DeleteBranch`.
Merging PR may fail because of various problems. The pull request may
have a dirty state because there is no transaction when merging a pull
request. ref
https://github.com/go-gitea/gitea/pull/25741#issuecomment-2074126393
This PR moves all database update operations to post-receive handler for
merging a pull request and having a database transaction. That means if
database operations fail, then the git merging will fail, the git client
will get a fail result.
There are already many tests for pull request merging, so we don't need
to add a new one.
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Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
