Fixed extractor decoding

Author: gplanchat

src/Extractor.php

@@ -70,7 +70,7 @@ public function extract(): iterable
             $message = $this->channel->get($this->topic);
             $this->channel->ack($message);
 
-            yield new AcceptanceResultBucket($message);
+            yield new AcceptanceResultBucket(\json_decode($message->content, true));
         }
     }
 }