Fix possible migration hazard, not in cache if no cache

Author: AlanCoding

ansible_base/rbac/models/content_type.py

@@ -143,7 +143,7 @@ def get_by_natural_key(self, *args: str) -> "DABContentType":
             kwargs = {'service__in': [get_local_resource_prefix(), 'shared'], 'app_label': app_label, 'model': model}
             # This ask here is actually ambiguous, so we try this extra lookup
             shared_key = ('shared', app_label, model)
-            if ('shared', app_label, model) in self._cache[self.db]:
+            if (self.db in self._cache) and (('shared', app_label, model) in self._cache[self.db]):
                 return self._cache[self.db][shared_key]
         else:
             service, app_label, model = args