Keba P40 Energy Limit Scaling Bug

### Description Thanks for the many integrations. Unfortunately, I encountered an issue with the Keba P40 integration. The energy limit is off by a factor of 10. Looking into the code, the issue seems to be already known during code writing. ``` java new FC6WriteRegisterTask(5010, // TODO Scalefactor for Unit: 10 Wh m(EvseKeba.ChannelId.SET_ENERGY_LIMIT, new UnsignedWordElement(5010))), ``` Line 204 in https://github.com/OpenEMS/openems/blob/develop/io.openems.edge.evse.chargepoint.keba/src/io/openems/edge/evse/chargepoint/keba/modbus/EvseKebaModbusImpl.java I would propose adding a constant like SCALE_FACTOR_0_10 in order to fix this bug. ### Screenshots _No response_ ### Operating System _No response_ ### How to reproduce the Error? Using the Keba P40 implementation and setting the energy limit with the openems charging station controller