Prevent clutter for frequently force-pushed MR branches
Currently, If you
**a)** use WIP merge requests (or the notion that unassigned merge requests are still under construction) and
**b)** use force pushing to keep the history clean as also the [Gitlab blog reccomends it](https://about.gitlab.com/blog/2018/06/07/keeping-git-commit-history-clean/),
your remote repository and your MR view will soon be polluted because all the previous force pushes are kept. See this extreme but real-world screenshot from one of our MRs. The scrollbar indicates how long this list of added commits, rewritten commits, ... is:

There should be a button on the MR view which reads "clean up rewritten commits" which
- removes all the unnecessary commit information from the MR overview
- removes all the unnecessary commits from the bare git repository
- removes all pipelines related to these deleted commits
issue