Migrate edit merge request button to pajamas component

What does this MR do and why?

Migrate edit merge request button to pajamas component

Screenshots or screen recordings

Before	After

How to set up and validate locally

• Go to merge request
• Look at Edit button in upper right corner

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.