Explicitly say when MR has been approved by me

Release notes

Problem to solve

As a reviewer of a merge request where other reviewers are involved, I don't clearly see that the MR has been approved by me.

Further details

When the MR has been approved by me, the Approve button changes to Revoke Approval. This communicate that I've already approved the MR, but this is not straightforward and it might be confusing, especially when there are many reviewers involved in the review. See screenshot:

Proposal

Change Merge request approved message to Merge request approved by you, Merge request approved by others, or Merge request approved by you and others, depending on the case.

/cc @pedroms