Replace jquery.get with Rails.ajax

In the code below jQuery.get is used in order to download javascript
that is then executed. In order to move away from jQuery ajax, we can
utilize Rails.ajax which does the same thing.

ee/app/assets/javascripts/projects/custom_project_templates.js

 import $ from 'jquery';
+import { Rails } from '~/lib/utils/rails_ujs';
 import projectNew from '~/projects/project_new';
 
 const bindEvents = () => {
@@ -125,13 +126,11 @@ export default () => {
   $groupTabContent.on('ajax:success', bindEvents);
 
   $navElement.one('click', () => {
-    // eslint-disable-next-line no-jquery/no-ajax
-    $.get($tabContent.data('initialTemplates'));
+    Rails.ajax({ url: $tabContent.data('initialTemplates'), type: 'GET' });
   });
 
   $groupNavElement.one('click', () => {
-    // eslint-disable-next-line no-jquery/no-ajax
-    $.get($groupTabContent.data('initialTemplates'));
+    Rails.ajax({ url: $groupTabContent.data('initialTemplates'), type: 'GET' });
   });
 
   bindEvents();