Fix lingering timer in lifx (home-assistant#92476)

* Fix lingering timer in lifx

* Remove duplicate code

homeassistant/components/lifx/light.py

@@ -170,9 +170,7 @@ def effect(self) -> str | None:
 
     async def update_during_transition(self, when: int) -> None:
         """Update state at the start and end of a transition."""
-        if self.postponed_update:
-            self.postponed_update()
-            self.postponed_update = None
+        self._cancel_postponed_update()
 
         # Transition has started
         self.async_write_ha_state()
@@ -327,6 +325,17 @@ async def async_added_to_hass(self) -> None:
         )
         return await super().async_added_to_hass()
 
+    def _cancel_postponed_update(self) -> None:
+        """Cancel postponed update, if applicable."""
+        if self.postponed_update:
+            self.postponed_update()
+            self.postponed_update = None
+
+    async def async_will_remove_from_hass(self) -> None:
+        """Run when entity will be removed from hass."""
+        self._cancel_postponed_update()
+        return await super().async_will_remove_from_hass()
+
 
 class LIFXWhite(LIFXLight):
     """Representation of a white-only LIFX light."""