Adds hoverstates for collapsed Issue/Merge Request sidebar

This MR is part 1/2 of https://gitlab.com/gitlab-org/gitlab-ce/issues/25011

What does this MR do?

Adds hoverstates for collapsed Issue/Merge Request sidebar

Are there points in the code the reviewer needs to double check?

Why was this MR needed?

We needed hover states on the issue/merge request sidebar

Screenshots (if relevant)

Does this MR meet the acceptance criteria?

• Changelog entry added
• Documentation created/updated
• API support added
• Tests
  • Added for this feature/bug
  • All builds are passing
• Conform by the merge request performance guides
• Conform by the style guides
• Branch has no merge conflicts with master (if it does - rebase it please)
• Squashed related commits together

What are the relevant issue numbers?

Closes #25011 (closed)

Added 1 commit:

• 17e8a7fe - Adds hoverstates for collapsed Issue/Merge Request sidebar

Compare with previous version

@fatihacet This is ready to be put in :)

https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/918 is part of this as well! Assigned them both to you!

Reassigned to @fatihacet

@fatihacet assigning back to myself for now ;)

Reassigned to @dimitrieh

Mentioned in issue #25011 (closed)

Added 97 commits:

• 17e8a7fe...a7a3636d - 96 commits from branch master
• 30c3eed8 - Adds hoverstates for collapsed Issue/Merge Request sidebar

Compare with previous version

@cperessini added the avatar hoverstate :)

@fatihacet ready for 🤘

Reassigned to @fatihacet

Status changed to merged

Mentioned in commit 8f98b704

Thanks @dimitrieh This looks shinny 🌞

Resolved all discussions

mentioned in merge request gitlab-com/www-gitlab-com!4007 (merged)