Adding curl error code 18 to retry behavior
check exception class

I got this fatal error today : PHP Fatal error:  Call to undefined method Guzzle\Http\Exception\ServerErrorResponseException::getCurlHandle() in /home/frontoffice/instances/lekino-video_web/shared/vendor/guzzle/guzzle/src/Guzzle/Plugin/Backoff/BackoffPlugin.php on line 95