[css-color-4][editorial] wpt cleanup, deleted tests

Author: svgeesus

css-color-4/Overview.bs

@@ -6309,8 +6309,6 @@ t422-rgba-func-int-a.xht
 t422-rgba-func-no-mixed-f.xht
 t422-rgba-func-pct-a.xht
 t422-rgba-func-whitespace-b.xht
-t422-rgba-onscreen-b.xht
-t422-rgba-onscreen-multiple-boxes-c.xht
 t422-rgba-values-meaning-b.xht
 t423-transparent-1-a.xht
 t423-transparent-2-a.xht
@@ -6336,8 +6334,6 @@ t424-hsl-values-b-9.html
 t425-hsla-basic-a.xht
 t425-hsla-clip-outside-device-gamut-b.xht
 t425-hsla-h-rotating-b.xht
-t425-hsla-onscreen-b.xht
-t425-hsla-onscreen-multiple-boxes-c.xht
 t425-hsla-parsing-f.xht
 t425-hsla-values-b.xht
 t43-svg-keywords-a.xht