Add search to audit event type filter

What does this MR do and why?

This allows the user to search by audit event type name in the GlCollapsibleListbox. This is really useful because the list contains 231 types at the moment.

In a next iteration, grouping will be added to the GlCollapsibleListbox which will facilitate finding audit event types even further.

Screenshots or screen recordings

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

Before	After

How to set up and validate locally

Make sure you have an EE license

1. Go to any group
2. Go to "Secure" > "Audit events"
3. Click "Streams" tab
4. Create a new streaming destination by clicking "Add streaming destination"
5. Provide a "Destination URL" and click the "Filter by stream event" accordion
6. Click the listbox
7. Validate it has a search box
8. Validate that typing in the search box filters the audit event types
9. Validate that the casing of the search term is irrelevant for the filtering
10. Validate that if your search term does not match any result, it displays "No results found"

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.