R1:1f311d64c608

Give Drydock resources and leases a real "destroy" lifecycle phase

Summary: Ref T9252. Some leases or resources may need to remove data, tear down VMs, etc., during cleanup. After they are released, queue a "destroy" phase for performing teardown.

Test Plan:
- Used `bin/drydock lease ...` to create a working copy lease.
- Used `bin/drydock release-lease` and `bin/drydock release-resource` to release the lease and then the working copy and host.
- Saw working copy and host get destroyed and cleaned…