Merge branch 'jnnkl-remove-eventlistener-show-index' into 'master'

Remove obsolete DOMContentLoadedEventListener

See merge request gitlab-org/gitlab!55624

app/assets/javascripts/pages/search/show/index.js

 import { initSearchApp } from '~/search';
 
-document.addEventListener('DOMContentLoaded', () => {
-  initSearchApp();
-});
+initSearchApp();