Merge branch 'fix-contextual-sidebar-null-binding-error' into 'master'

Fix contextual_sidebar null function binding

Closes #56394

See merge request gitlab-org/gitlab-ce!24408

app/assets/javascripts/contextual_sidebar.js

@@ -70,7 +70,7 @@ export default class ContextualSidebar {
       ContextualSidebar.setCollapsedCookie(collapsed);
     }
 
-    requestIdleCallback(this.toggleSidebarOverflow);
+    requestIdleCallback(() => this.toggleSidebarOverflow());
   }
 
   toggleSidebarOverflow() {