Don't call power_update() twice

it is called as part of energy_update()

Author: bouwew

plugwise_usb/nodes/circle.py

@@ -1256,7 +1256,8 @@ async def get_state(self, features: tuple[NodeFeature]) -> dict[NodeFeature, Any
                 case NodeFeature.RELAY_INIT:
                     states[feature] = self._relay_config
                 case NodeFeature.POWER:
-                    states[feature] = await self.power_update()
+                    # power_update() is called as part of energy_update()
+                    states[feature] = self._power
                     _LOGGER.debug(
                         "async_get_state %s - power: %s",
                         self._mac_in_str,