Handle waiter already done in zeroconf service info (#374)

aiohomekit/zeroconf.py

@@ -386,7 +386,7 @@ def _async_handle_loaded_service_info(self, info: AsyncServiceInfo) -> None:
 
         if waiters := self._waiters.pop(description.id, None):
             for waiter in waiters:
-                if not waiter.cancelled():
+                if not waiter.cancelled() and not waiter.done():
                     waiter.set_result(discovery)
 
     @abstractmethod