Add report abuse category to comments on issues & MRs

What does this MR do and why?

• Asks user to select an abuse category before they are redirected to the standard report abuse form, when they are reporting a comment posted on an Issue or an MR.
• This change will be added to comments posted on Commits or Snippets in a follow-up MR, in order to reduce the number of changes.

Code changes explained:

• Earlier each note would have it's own reportAbusePath attached to it, this would be of the format /abuse_reports/new?ref_url={note_url}&user_id={author_id}. When a user would click on the report abuse button, they would be redirected to this URL.
• Now, we want to trigger the AbuseCategorySelector which is a side-drawer to ask users to select the abuse category first. This drawer accepts the reportAbusePath which is now a fixed path /abuse_reports/add_category (and hence can be injected), and 2 props - authorId and noteUrl. Hence, each note doesn't need to have it's own reportAbusePath anymore.

Screenshots or screen recordings

Issue	Merge Request	Commit (un-changed)
issue	merge-request	commit

How to set up and validate locally

1. Log-in as a user and post comments on an issue and merge request.
2. Log-in as another user, navigate to the comment, then click on ︙ > Report abuse to administrator

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.

Resolves gitlab-org/modelops/anti-abuse/team-tasks#192