fix: added serializer_class to views needed

core/apps/contracts/views/owners.py

@@ -61,6 +61,7 @@ class ContractOwnerViewSet(BaseViewSetMixin, ModelViewSet):
 @extend_schema(tags=["Contract Files"])
 class ContractOwnerAttachedFileApiView(BaseApiViewMixin, GenericAPIView):  # type: ignore
     permission_classes = [AllowAny]
+    serializer_class = ListContractOwnerSerializer
     queryset = ContractOwnerModel.objects.all()
 
     method_permission_classes = {"delete": [AllowAny]}