Filter abuse reports by user

What does this MR do?

Adds ability to filter abuse reports by user in admin area. This will allow admin to act on the report of a particular user.

Partly addresses #35244 (closed)

Screenshots

I followed the same UI style as Audit Log page for adding grey bar with filter.

Before	After

More screenshots:

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• [-] Documentation created/updated or follow-up review issue created
• Code review guidelines
• Merge request performance guidelines
• Style guides
• [-] Database guides
• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers