Remove setting self.gateway_id from gw_data

Author: bouwew

plugwise/__init__.py

@@ -320,7 +320,6 @@ async def async_update(self) -> PlugwiseData:
         data = PlugwiseData(devices={}, gateway={})
         try:
             data = await self._smile_api.async_update()
-            self.gateway_id = data.gateway["gateway_id"]
         except (DataMissingError, KeyError) as err:
             raise PlugwiseError("No Plugwise data received") from err