Inventor Eva Ion Pro: water_level needs to be optional

water_level seems to not be reported in some circumstances.

Issue #1839

custom_components/tuya_local/devices/inventor_evaionpro_dehumidifier.yaml

@@ -61,6 +61,7 @@ primary_entity:
       name: pump
     - id: 104
       type: integer
+      optional: true
       name: water_level
 secondary_entities:
   - entity: fan