Add service ping to support tracking runner maintenance notes

What does this MR do and why?

This MR adds a service ping to support tracking runners created with maintenance notes.

Changelog: other

Closes #354756 (closed)

MR acceptance checklist

Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

Screenshots or screen recordings

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How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

1. Monitor the events with rails runner scripts/internal_events/monitor.rb runner_created_with_maintenance_note (Follow setup steps from https://docs.gitlab.com/ee/development/internal_analytics/internal_event_instrumentation/local_setup_and_debugging.html if needed)

2. Visit http://gdk.test:3000/admin/runners and create a new runner. Check that the counts.count_total_runner_created_with_maintenance_note_monthly and counts.count_total_runner_created_with_maintenance_note_weekly metrics have increased by 1.

   

3. Create a runner using a registration token and specify a maintenance note. Check that the counts.count_total_runner_created_with_maintenance_note_monthly and counts.count_total_runner_created_with_maintenance_note_weekly metrics have increased by 1.

   

4. Same can be done for other scopes, for instance in a project: