Add filter controls to the Merge Request Analytics page

What does this MR do?

This MR adds filter controls to the Merge Request Analytics (aka. throughput) page.

Screenshots

Before:	After:

Does this MR meet the acceptance criteria?

Conformity

• [-] Changelog entry
• [-] Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• [-] Database guides
• Separation of EE specific content

Availability and Testing

To test this out enable this feature flag in rails c with Feature.enable(:project_merge_request_analytics) and navigate to this URL and see that all filters are applied:

• http://127.0.0.1:3000/flightjs/flight/-/analytics/merge_request_analytics?milestone_title=v2.0&label_name[]=Afterpod&author_username=joi&assignee_username=tien

To get MRs to show up you can run the following in the rails c:

project = Project.find_by_full_path("flightjs/flight")
project.merge_requests.each {|mr| print mr.update!(state_id: 3) }
project.merge_requests.each {|mr| print mr.metrics.update!(merged_at: Time.now) }

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers
• [-] Informed Infrastructure department of a default or new setting change, if applicable per definition of done

Security

If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:

• [-] Label as security and @ mention @gitlab-com/gl-security/appsec
• [-] The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
• [-] Security reports checked/validated by a reviewer from the AppSec team

Related to #229266 (closed) Closes #230287 (closed)