Cleanup mqtt PLATFORMS constant and CI-test platform filters (#112847)

tests/components/mqtt/test_light_template.py

@@ -42,7 +42,6 @@ from homeassistant.const import (
     STATE_OFF,
     STATE_ON,
     STATE_UNKNOWN,
-    Platform,
 )
 from homeassistant.core import HomeAssistant, State
 
@@ -94,13 +93,6 @@ DEFAULT_CONFIG = {
 }
 
 
-@pytest.fixture(autouse=True)
-def light_platform_only():
-    """Only setup the light platform to speed up tests."""
-    with patch("homeassistant.components.mqtt.PLATFORMS", [Platform.LIGHT]):
-        yield
-
-
 @pytest.mark.parametrize(
     "hass_config",
     [