Fixes port missing in log issue #925

Author: ezimuel

src/Elasticsearch/Connections/Connection.php

@@ -422,7 +422,7 @@ public function logRequestFail(array $request, array $response, \Exception $exce
             array(
                 'method'    => $request['http_method'],
                 'uri'       => $response['effective_url'],
-                'port'      => $response['transfer_stats']['primary_port'],
+                'port'      => $response['transfer_stats']['primary_port'] ?? '',
                 'headers'   => $request['headers'],
                 'HTTP code' => $response['status'],
                 'duration'  => $response['transfer_stats']['total_time'],