Apply patch file as suggestion in Merge Request
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## Problem to Solve
Sometimes suggestions are not sufficient for complex change suggestions in a merge request. In these cases reviewers may provide a patch file for the author to help aid in the review process. Users who are given a patch file must copy/paste the contents of the patch to their project or apply the patch through git commands. Both of those options require the user to leave the merge request.
## Proposal
When a [patch is rendered](https://gitlab.com/gitlab-org/gitlab/-/issues/233107) inside of a merge request comment we should add an option to "Apply Patch" so that users have a one click process to implement the suggested change.
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