allow nullable response init

src/Client/Response.php

@@ -10,7 +10,9 @@ class Response
     private ?string $_meta = null;
     private ?string $_body = null;
 
-    public function __construct(string $data)
+    public function __construct(?string $data = null)
+    {
+        if ($data)
         {
             $match = [];
 
@@ -46,6 +48,7 @@ class Response
                 );
             }
         }
+    }
 
     public function setCode(?int $value): void
     {