TASK: Shorten code

* Do not use variable, instead provide result to method call.
* Do not provide public method which is not part of API. Otherwise one
  might use it in custom PHP code and switch connection later on. Then the
  method call will no longer work.

Classes/Connection/Elasticsearch.php

@@ -179,17 +179,16 @@ public function deleteIndex()
 
     public function deleteIndexByDocumentType(string $documentType)
     {
-        $query = Query::create([
+        $this->deleteIndexByQuery(Query::create([
             'query' => [
                 'term' => [
-                    'search_document_type' => $documentType
-                ]
-            ]
-        ]);
-        $this->deleteIndexByQuery($query);
+                    'search_document_type' => $documentType,
+                ],
+            ],
+        ]));
     }
 
-    public function deleteIndexByQuery(Query $query)
+    private function deleteIndexByQuery(Query $query)
     {
         $index = $this->connection->getClient()->getIndex($this->indexFactory->getIndexName());
         if (!$index->exists()) {