This PR updates the test database schema files in Collab with a warning
about adding the corresponding database migration in Cloud before
merging any changes.

This should pair with the Danger warning to provide additional
signposting (and also for agents who may be modifying the files).

Includes the re-dumped schema for the addition of the `language_name`
column on the `language_servers` table.

Release Notes:

- N/A