Correct path to libraries folder

Closes #3476811

datatables.module

@@ -220,7 +220,7 @@ function datatables_requirements($phase) {
   $requirements = [];
 
   if ($phase == 'runtime') {
-    $library_path = DRUPAL_ROOT . '/libraries/datatables/datatables';
+    $library_path = DRUPAL_ROOT . '/libraries/datatables';
     if (!file_exists($library_path)) {
       $requirements['datatables_assets'] = [
         'title' => t('DataTables Assets'),