Avatto CLS02: calibration dp should be optional

Assume this is not sent when not calibrating.

custom_components/tuya_local/devices/avatto_cls02_curtainduallights.yaml

@@ -159,6 +159,7 @@ entities:
     dps:
       - id: 108
         type: integer
+        optional: true
         name: value
         unit: "%"
         range: