Remove rfxtrx signal repetition (#67675)

homeassistant/components/rfxtrx/__init__.py

homeassistant/components/rfxtrx/config_flow.py

homeassistant/components/rfxtrx/const.py

homeassistant/components/rfxtrx/cover.py

homeassistant/components/rfxtrx/light.py

homeassistant/components/rfxtrx/siren.py

homeassistant/components/rfxtrx/strings.json

homeassistant/components/rfxtrx/switch.py

tests/components/rfxtrx/test_config_flow.py

tests/components/rfxtrx/test_cover.py

tests/components/rfxtrx/test_device_action.py

tests/components/rfxtrx/test_device_trigger.py

tests/components/rfxtrx/test_light.py

tests/components/rfxtrx/test_siren.py

tests/components/rfxtrx/test_switch.py