Change all components to use the same error page in web UI (#24512)

app/javascript/mastodon/features/ui/util/async-components.js

@@ -82,10 +82,6 @@ export function FollowRequests () {
   return import(/* webpackChunkName: "features/follow_requests" */'../../follow_requests');
 }
 
-export function GenericNotFound () {
-  return import(/* webpackChunkName: "features/generic_not_found" */'../../generic_not_found');
-}
-
 export function FavouritedStatuses () {
   return import(/* webpackChunkName: "features/favourited_statuses" */'../../favourited_statuses');
 }