[css-color-4] more wpt

Author: svgeesus

css-color-4/Overview.bs

@@ -4489,6 +4489,7 @@ Transparency: the 'opacity' property</h2>
 		composited-filters-under-opacity.html
 		filters-under-will-change-opacity.html
 		animation/color-composition.html
+		animation/opacity-interpolation.html
 	</wpt>
 
 	<dl>