Bulk removal of stale branches in a project
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## Problem to Solve
It's possible that a project many have many stale branches that are no longer needed in a project. On the `branches` page GitLab lists stale branches and provides a way to individually remove them, but there is no bulk removal option.
### Additional details
There is currently an option to [delete merged branches](https://docs.gitlab.com/ee/user/project/repository/branches/#delete-merged-branches).
## Proposal
On the branches page (and via the API) an additional button should be added that allows you to bulk delete stale branches.
issue