Problem

With the change on #3644 (particularly b6863f1, released on PostgREST v13) schema-based multi-tenancy becomes more complicated as the user has to remember to remove schemas from db-schemas once DROP SCHEMA is done, otherwise PostgREST will fail.

Proposal 1

Automate schema removal by extending the Finer-Grained Event Trigger.

Proposal 2

Rollback to becoming lenient and don't fail on nonexistent schemas on db-schemas.