Tests

Add management command to clean up unreferenced bucket objects #1631

Job	Run time
Lint	31s
Docker tests	2m 19s
Compatibility tests (3.10, sqlite)	1m 24s
Compatibility tests (3.10, postgres)	1m 30s
Compatibility tests (3.10, mysql)	1m 35s
Compatibility tests (3.11, sqlite)	1m 20s
Compatibility tests (3.11, postgres)	1m 22s
Compatibility tests (3.11, mysql)	1m 23s
Compatibility tests (3.12, sqlite)	1m 22s
Compatibility tests (3.12, postgres)	1m 24s
Compatibility tests (3.12, mysql)	1m 23s
	15m 33s

Provide feedback