Clear dispatches after waiting for them to stop

Signed-off-by: Mathias L. Baumann <[email protected]>

Author: Marenz

src/frequenz/dispatch/_dispatcher.py

@@ -212,6 +212,8 @@ async def wait(self) -> None:
         """Wait until all actor dispatches are stopped."""
         await asyncio.gather(self._bg_service.wait(), self._empty_event.wait())
 
+        self._actor_dispatchers.clear()
+
     @override
     def cancel(self, msg: str | None = None) -> None:
         """Stop the local dispatch service."""
@@ -220,8 +222,6 @@ def cancel(self, msg: str | None = None) -> None:
         for instance in self._actor_dispatchers.values():
             instance.cancel()
 
-        self._actor_dispatchers.clear()
-
     async def start_dispatching(
         self,
         dispatch_type: str,