Update color-5.vim

https://www.w3.org/TR/2024/WD-css-color-5-20240229/

test/test.css

@@ -100,6 +100,8 @@
 .color-5 {
 	display: device-cmyk(0, 81%, 81%, 30%);
 	display: color-mix(red yellow 65%);
+	display: light-dark(white, black);
+	display: contrast-color(red max);
 }
 
 @color-profile swopc {