Update CHANGELOG.md

Author: photonstorm

CHANGELOG.md

@@ -5,6 +5,7 @@
 ### Bug Fixes
 
 * The Spine Plugin was not clearing down the resize event listener in WebGL, causing it to still fire even if the Scene was closed. Fix #4808 (thanks @RollinSafary)
+* When a game is created with the HEADLESS renderer, `Game.destroy()` had no effect and the game kept on running. Now it destroys itself properly. Fix #4804 (thanks @samme)
 
 ## Version 3.20.1 - Fitoria - 15th October 2019