code: public static String getMessageJson(Object message) {
          VersionedMessage<?> versionedMessage = new VersionedMessage<>(CURRENT_MESSAGE_VERSION, message);
  
          return GSON.toJson(versionedMessage);
      }
docs: Get the notification message JSON from the given object.
  
  @param message  the message in object form
  
  @return the message as a JSON string