fix unit tests

Author: ignacio

deepaas/tests/test_v2_models.py

@@ -171,7 +171,7 @@ async def test_dummy_model_with_wrapper(self, m_clean):
         task = w.train(sleep=0)
         await task
         ret = task.result()
-        self.assertIsNone(ret)
+        self.assertIsNone(ret['output'])
         meta = w.get_metadata()
         self.assertIn("description", meta)
         self.assertIn("id", meta)