Royal air conditioner: use quotes in string mapping

custom_components/tuya_local/devices/royal_airconditioner.yaml

@@ -41,13 +41,13 @@ primary_entity:
       name: fan_mode
       type: string
       mapping:
-        - dps_val: 0
+        - dps_val: "0"
           value: auto
-        - dps_val: 3
+        - dps_val: "3"
           value: low
-        - dps_val: 2
+        - dps_val: "2"
           value: medium
-        - dps_val: 1
+        - dps_val: "1"
           value: high
     - id: 8
       name: preset_mode_eco