Use vcrpy for tests to simulate PDC responses.

tests/test_scheduler/test_module_wait.py

@@ -24,7 +24,7 @@ import unittest
 import mock
 import module_build_service.messaging
 import module_build_service.scheduler.handlers.modules
-
+import modulemd as _modulemd
 
 class TestModuleWait(unittest.TestCase):
 
@@ -50,6 +50,9 @@ class TestModuleWait(unittest.TestCase):
             'state': 'some state',
         }
 
+        mmd = _modulemd.ModuleMetadata()
+        mocked_module_build.mmd.return_value = mmd
+
         from_module_event.return_value = mocked_module_build
 
         msg = module_build_service.messaging.RidaModule(msg_id=None, module_build_id=1,