* Fix possible race conditions when suspending/unsuspending accounts
* Fix tests
Tests were assuming SuspensionWorker and UnsuspensionWorker would do the
suspending/unsuspending themselves, but this has changed.
Fix issue #16603 undefined method `serialize_payload' for Unsuspend Account Service error.
It seems that this service forgot to `include Payloadable` so that `serialize_payload` could not be found in this service.
Nginx can be configured to bypass proxy cache when a special header
is in the request. If the response is cacheable, it will replace
the cache for that request. Proxy caching of media files is
desirable when using object storage as a way of minimizing bandwidth
costs, but has the drawback of leaving deleted media files for
a configured amount of cache time. A cache buster can make those
media files immediately unavailable. This especially makes sense
when suspending and unsuspending an account.
