[predicates] fix paginated_rset when the class has no page_size_property Fixes test failure introduced by 70733b2dfd2a, which assumed paginated_rset would only be called on a class with a page_size_property attribute.

sync_schema_props_perms('cwuri')

helper = repo.system_source.dbhelper
cu = session.cnxset.cu
helper.set_null_allowed(cu, 'moved_entities', 'extid', 'VARCHAR(256)', False)

commit()