Added Redis HLL tracking to post merge actions

What does this MR do and why?

Adds tracking events to the merge request widgets post merge action buttons.

Screenshots or screen recordings

How to set up and validate locally

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.

Closes #343123 (closed)