Fix a small typo in css-scroll-snap Overview.bs (#6505)

Author: mrobinson

css-scroll-snap-1/Overview.bs

@@ -430,7 +430,7 @@ Re-snapping After Layout Changes</h4>
     however, is UA-defined.
     The UA may, for example,
     when snapped to the start of a section,
-    choose not to animation the scroll to the section’s new position
+    choose not to animate the scroll to the section’s new position
     as content is dynamically added earlier in the document
     in order to create the illusion of not scrolling.