[css-values-4][editorial] correct autolink for color functions

Author: svgeesus

css-values-4/Overview.bs

@@ -2918,7 +2918,7 @@ Functional Notations</h2>
 
 	The [=math functions=] are defined below.
 	Other [=functional notations=] are defined in their own modules;
-	for example the [=absolute-color-function|color functions=] are defined in [[CSS-COLOR-4]].
+	for example the [= absolute-color-function|color functions=] are defined in [[CSS-COLOR-4]].
 
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