Remove nested Promise from project select

app/assets/javascripts/project_select.js

@@ -5,9 +5,7 @@ import Api from './api';
 import ProjectSelectComboButton from './project_select_combo_button';
 import { s__ } from './locale';
 
-export default function projectSelect() {
-  import(/* webpackChunkName: 'select2' */ 'select2/select2')
-    .then(() => {
+const projectSelect = () => {
   $('.ajax-project-select').each(function(i, select) {
     var placeholder;
     const simpleFilter = $(select).data('simpleFilter') || false;
@@ -101,6 +99,9 @@ export default function projectSelect() {
     if (simpleFilter) return select;
     return new ProjectSelectComboButton(select);
   });
-    })
+};
+
+export default () =>
+  import(/* webpackChunkName: 'select2' */ 'select2/select2')
+    .then(projectSelect)
     .catch(() => {});
-}