[hooks] Delete binary DO when deleting an archive unit not related to a profile
We extend the logic of "seda.doref.del" hook so that it not only handles the case of "simplified profile" but also the case of archive unit not related to a profile. In the later case, we check that the container of "SEDABinaryDataObject" is really a "SEDAArchiveUnit" (not sure what else it could be) and trigger the operation deleting the binary data-object when its parent object reference (SEDADataObjectReference entity) is deleted. Accordingly, we rename hook and operation classes and update their docstring. This resolves CONSEJIRA-643 but making deletion of an archive unit containing a binary data object but not related to profile. New test goes into test_schema.py below other tests related to the hook we modified.