php notice fix in materio_decoupled

web/modules/custom/materio_decoupled/materio_decoupled.module

@@ -36,6 +36,7 @@ function materio_decoupled_page_attachments(array &$attachments) {
   $entity_type = null;
   $entity_bundle = null;
   $entity_id = null;
+  $entity_uuid = null;
   foreach (['node', 'taxonomy_term'] as $type) {
     $entity = \Drupal::routeMatch()->getParameter($type);
     if($entity){