BUGFIX: Do not escape unicode characters for fulltext search

For details see: https://discuss.neos.io/t/elasticsearch-special-chars-umlauts/4869

Author: daniellienert

Classes/Eel/ElasticSearchQueryBuilder.php

@@ -1,5 +1,4 @@
 <?php
-
 declare(strict_types=1);
 
 namespace Flowpack\ElasticSearch\ContentRepositoryAdaptor\Eel;
@@ -669,7 +668,7 @@ public function count()
     public function fulltext($searchWord, array $options = [])
     {
         // We automatically enable result highlighting when doing fulltext searches. It is up to the user to use this information or not use it.
-        $this->request->fulltext(trim(json_encode($searchWord), '"'), $options);
+        $this->request->fulltext(trim(json_encode($searchWord, JSON_UNESCAPED_UNICODE), '"'), $options);
         $this->request->highlight(150, 2);
 
         return $this;