Moving stop to another try except, to avoid skipping cancellation of …

…tasks on shutdown.

mango/agent/core.py

@@ -4,6 +4,7 @@
 Every agent must live in a container. Containers are responsible for making
  connections to other agents.
 """
+
 import asyncio
 import logging
 from abc import ABC
@@ -464,7 +465,10 @@ async def shutdown(self):
             self._check_inbox_task.remove_done_callback(self.raise_exceptions)
             self._check_inbox_task.cancel()
             await self._check_inbox_task
+        except asyncio.CancelledError:
+            pass
 
+        try:
             await self._scheduler.stop()
         except asyncio.CancelledError:
             pass