Tables dropped: 
 * application_services, 
 * application_services_regex, 
 * transaction_id_to_pdu, 
 * stats_reporting
 * current_state_resets
 * event_content_hashes
 * event_destinations
 * event_edge_hashes
 * event_signatures
 * feedback
 * room_hosts
 * state_forward_extremities