BHT002 GBLW thermostat: add additional Heat state

Some compatible devices seem to use Heat instead of Warming (or perhaps in
slightly different circumstance).

Issue #2386

custom_components/tuya_local/devices/bht002_gblw_thermostat.yaml

@@ -34,6 +34,8 @@ primary_entity:
               mapping:
                 - dps_val: Warming
                   value: heating
+                - dps_val: Heat
+                  value: heating
                 - dps_val: "Off"
                   value: idle
                 - dps_val: Closed