<!-- Title suggestion: <async-index-name> synchronous database index(es) addition/removal -->

## Summary

This issue is to add a migration(s) to create/destroy the `<async-index-name>` database index(es) synchronously after it has been created/destroyed on GitLab.com.

The asynchronous index(es) was introduced in <!-- Link to MR that introduced the asynchronous index -->.

/assign me
/due in 2 weeks
/label ~database ~"type::maintenance" ~"maintenance::scalability"
