Update Client.php (#323)

Add the possibility to send a format array of data to JSON with Guzzle (https://docs.guzzlephp.org/en/stable/request-options.html#json

Author: MathieuMenegain

src/Omniphx/Forrest/Client.php

@@ -226,6 +226,12 @@ private function handleRequest()
         } else {
             unset($this->parameters['query']);
         }
+        
+        if (isset($this->options['json'])) {
+            $this->parameters['json'] = $this->options['json'];
+        } else {
+            unset($this->parameters['json']);
+        }
 
         try {
             $response = $this->httpClient->request($this->options['method'], $this->url, $this->parameters);