Fix cs issues

Closes #3358408

modules/select2_facets/src/Plugin/facets/widget/Select2Widget.php

@@ -129,7 +129,7 @@ class Select2Widget extends WidgetPluginBase implements ContainerFactoryPluginIn
     }
 
     $build['#items'] = [
-      $element
+      $element,
     ];
     return $build;
   }