Update plugin_solinteg.py

Author: rosenrot00

custom_components/solax_modbus/plugin_solinteg.py

@@ -1176,6 +1176,7 @@ class SolintegModbusSensorEntityDescription(BaseModbusSensorEntityDescription):
         key="battery_soc",
         native_unit_of_measurement=PERCENTAGE,
         device_class=SensorDeviceClass.BATTERY,
+        state_class=SensorStateClass.MEASUREMENT,
         register=33000,
         scale=0.01,
         rounding=2,