fix anonymous user

apps/establishment/views/back.py

@@ -878,6 +878,8 @@ class AdminEmployeeListView(generics.ListAPIView):
 
     def get_queryset(self):
         user = self.request.user
+        if user.is_anonymous:
+            return None
         est_ids = models.Establishment.objects.filter(
             userrole__user=user,
             userrole__role__role=Role.ESTABLISHMENT_ADMINISTRATOR,