fix keepalive

Author: bj00rn

src/publisher/mqtt_publisher.py

@@ -114,6 +114,7 @@ async def __on_connect(self) -> None:
         if not self.first_connection:
             await self.__enable_commands()
         self.first_connection = False
+        self.keepalive()
 
     @override
     def enable_commands(self) -> None: