Added popover to approvals for when a user has committed

What does this MR do and why?

This adds a popover to the approvals widget in the merge request widget for when the setting to disable committer approvals is enabled and the current user has committed a change on the merge request.

Screenshots or screen recordings

How to set up and validate locally

• Enable Prevent approvals by users who add commits in merge request project settings
• Open a merge request from a different user
• Create a commit on that merge request
• See the popover link in the approvals widget

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

#372769 (closed)