Remove the validation code from the storage iff the reference count is 0.
This is better than removing the storage directly, because it will not remove the code
that was suddenly got used by some parachain while this dispatchable was pending
dispatching.
Remove the validation code from the storage iff the reference count is 0.
This is better than removing the storage directly, because it will not remove the code that was suddenly got used by some parachain while this dispatchable was pending dispatching.