Update Overview.bs

Typo

Author: davelab6

css-fonts-4/Overview.bs

@@ -2478,7 +2478,7 @@ according to the rules given in [[#localized-name-matching]].
 If no such named instance exists,
 this descriptor is treated as if it has a value of 'font-named-instance/auto'.
 Otherwise, this named instance's variation axis values
-are applied a this position in the [[#font-feature-variation-resolution]].
+are applied to this position in the [[#font-feature-variation-resolution]].
 
 <div class="example">
 For example, the following ''@font-face'' block will