Redirect maintainer contributing to a fork back to the MR

The following discussion from !212285 (merged) should be addressed:

• @vyaklushin started a discussion: (+2 comments)

  question (blocking) For scenario 2, after a maintainer edits a file in the merge request, the maintainer gets redirected to the blob view page in the fork. The user has to manually go back to the merge request to see the changes.

  Should we redirect the user back to the merge request after editing file to avoid backtracking? 🤔