Handle Managed Motorhead Data Key (#6169)

# Handle Managed Motorhead Data Key
Managed motorhead will return a payload with a `data` key. we need to
handle this to properly access messages from the server.

langchain/memory/motorhead_memory.py

@@ -48,6 +48,8 @@ class MotorheadMemory(BaseChatMemory):
             headers=self.__get_headers(),
         )
         res_data = res.json()
+        res_data = res_data.get("data", res_data)  # Handle Managed Version
+
         messages = res_data.get("messages", [])
         context = res_data.get("context", "NONE")