Show a list of open MR details in badge popover

What does this MR do and why?

This MR adds a popover that is being triggered when user hover/click on the MR badge. It fires a graphql query to fetch MR details and render them in the list.

This feature is behind filter_blob_path feature flag.

References

Please include cross links to any resources that are relevant to this MR. This will give reviewers and future readers helpful context to give an efficient review of the changes introduced.

• badge was add in !183118 (comment 2373778811)
• see #448868 (closed) description for more context

MR acceptance checklist

Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

Screenshots or screen recordings

Screenshots are required for UI changes, and strongly recommended for all other merge requests.

How to set up and validate locally

1. Enable filter_blob_path and blob_repository_vue_header_app flag in GDK
2. Open a file that has open MRs that
   • opened in the last 30 days
   • targeting the current branch

Related to #448868 (closed)