Use supported color modes in Axis integration (home-assistant#51557)

* Use supported color modes in Axis integration

* Fix Frencks comments

* Do Frencks suggestion

homeassistant/components/axis/light.py

@@ -4,7 +4,7 @@
 
 from homeassistant.components.light import (
     ATTR_BRIGHTNESS,
-    SUPPORT_BRIGHTNESS,
+    COLOR_MODE_BRIGHTNESS,
     LightEntity,
 )
 from homeassistant.core import callback
@@ -49,7 +49,8 @@ def __init__(self, event, device):
         self.current_intensity = 0
         self.max_intensity = 0
 
-        self._features = SUPPORT_BRIGHTNESS
+        self._attr_supported_color_modes = {COLOR_MODE_BRIGHTNESS}
+        self._attr_color_mode = COLOR_MODE_BRIGHTNESS
 
     async def async_added_to_hass(self) -> None:
         """Subscribe lights events."""
@@ -67,11 +68,6 @@ async def async_added_to_hass(self) -> None:
         )
         self.max_intensity = max_intensity["data"]["ranges"][0]["high"]
 
-    @property
-    def supported_features(self):
-        """Flag supported features."""
-        return self._features
-
     @property
     def name(self):
         """Return the name of the light."""