Triple monitoring powerstrip: update energy scale

Update scale to match Tuya docs with kWh units.

custom_components/tuya_local/devices/smart_powerstrip_3_outlet_energy.yaml

@@ -87,6 +87,8 @@ secondary_entities:
         type: integer
         unit: kWh
         optional: true
+        mapping:
+          - scale: 1000
       - id: 25
         type: integer
         name: calibration