Added more actions and report as abuse to all notes

What does this MR do?

Adds a "Report as abuse" feature to all notes.

Added the "More actions" dropdown to all notes.

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

Why was this MR needed?

Screenshots (if relevant)

For some reason I can't upload the gif, probably too big, its here: http://imgur.com/4AnCeMj

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• 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?

Half of https://gitlab.com/gitlab-org/gitlab-ce/issues/30281