Merge branch 'jnnkl-eventlistener-product-analytics-graphs' into 'master'

Remove obsolete DOMContentLoadedEventListener

See merge request gitlab-org/gitlab!53971

app/assets/javascripts/pages/projects/product_analytics/graphs/index.js

 import initActivityCharts from '~/analytics/product_analytics/activity_charts_bundle';
 
-document.addEventListener('DOMContentLoaded', () => initActivityCharts());
+initActivityCharts();