Remove obsolete DOMContentLoadedEventListener

app/assets/javascripts/pages/dashboard/projects/index/index.js

 import ProjectsList from '~/projects_list';
 import initCustomizeHomepageBanner from './init_customize_homepage_banner';
 
-document.addEventListener('DOMContentLoaded', () => {
-  new ProjectsList(); // eslint-disable-line no-new
-
-  initCustomizeHomepageBanner();
-});
+new ProjectsList(); // eslint-disable-line no-new
+initCustomizeHomepageBanner();