Fix heading id

Author: jakearchibald

css-view-transitions-1/Overview.bs

@@ -1019,7 +1019,7 @@ urlPrefix: https://html.spec.whatwg.org/multipage/rendering.html; type: dfn;
 			Issue: Define the algorithm used to clip the snapshot when it exceeds max size.
 	</div>
 
-## [=Setup transition pseudo-elements=] ## {#create-transition-pseudo-elements-algorithm}
+## [=Setup transition pseudo-elements=] ## {#setup-transition-pseudo-elements-algorithm}
 
 	<div algorithm>
 		To <dfn>setup transition pseudo-elements</dfn> for a {{ViewTransition}} |transition|: