Atomi string lights: fix colour mode mapping

Issue #255

custom_components/tuya_local/devices/atomi_string_lights.yaml

@@ -12,7 +12,7 @@ primary_entity:
         - dps_val: white
           value: color_temp
         - dps_val: colour
-          value: colour
+          value: rgbw
         - dps_val: scene1
           value: Strobe
         - dps_val: scene2