Limit scope of init_create_cluster module

Do not import the init_create_cluster package
in all project and group pages

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

+import initCreateCluster from '~/create_cluster/init_create_cluster';
+
+document.addEventListener('DOMContentLoaded', () => {
+  initCreateCluster(document, gon);
+});

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

 import Project from './project';
 import ShortcutsNavigation from '../../behaviors/shortcuts/shortcuts_navigation';
-import initCreateCluster from '~/create_cluster/init_create_cluster';
 
 document.addEventListener('DOMContentLoaded', () => {
-  initCreateCluster(document, gon);
-
   new Project(); // eslint-disable-line no-new
   new ShortcutsNavigation(); // eslint-disable-line no-new
 });