Avoid numbers with floating point rounding issues

Author: keithamus

tests/colors/0053/source.css

@@ -1,3 +1,3 @@
 a {
-  color: color(xyz-d65 0.23456 0.18765 0.56789);
+  color: color(xyz-d65 0.23456 0.18768 0.56789);
 }