Loratap curtain switch: Add continue to possible values.

Even though Home Assistant does not support it, it still may appear in the
dps from the device, and if so, we want to select the correct group of commands
to make available to the user.

custom_components/tuya_local/devices/loratap_curtain_switch.yaml

@@ -21,7 +21,7 @@ primary_entity:
                   value: close
                 - dps_val: "3"
                   value: stop
-            - dps_val: [ "open", "close", "stop" ]
+            - dps_val: [ "open", "close", "stop", "continue" ]
               mapping:
                 - dps_val: open
                   value: open