Add auditing of runner token reset operations

What does this MR do and why?

Describe in detail what your merge request does and why.

This MR adds auditing to the Ci::Runners::ResetRegistrationTokenService class. It does so by adding an EE version of ResetRegistrationTokenService and a supporting RunnersTokenAuditEventService class to allow creating audit log entries related to runner registration token changes.

NOTE: I have used the User model as the entity when resetting the runners token in ApplicationSetting because ApplicationSetting doesn't define #full_path (among other required properties), causing a crash in https://gitlab.com/gitlab-org/gitlab/blob/pedropombeiro%2F355637%2Flog-token-reset/ee/app/services/ee/audit_event_service.rb#L294-294. Not sure if there's a better approach?

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How to set up and validate locally

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1. Visit http://gdk.test:3000/admin/runners
2. Click the Register an instance runner button and then Reset registration token under it.
3. Visit http://gdk.test:3000/admin/audit_logs, a new log entry should be visible describing the action taken.
4. Visit a group runners settings page, e.g. http://gdk.test:3000/groups/gitlab-instance-80acc125/-/runners.
5. Click the Register a group runner button and then Reset registration token under it.
6. Visit http://gdk.test:3000/admin/audit_logs, a new log entry should be visible describing the action taken.

MR acceptance checklist

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Closes #355637 (closed)