docs: public void unregisterInstance(String serviceName, String instanceId, boolean isOwned){
          String uri = toInstanceUri(serviceName, instanceId) + "/" + isOwned;
          HttpResponse result = invoker.invoke(uri, null,
                  HttpMethod.DELETE);
  
          if (result.getHttpCode() != HTTP_OK) {
              throw new ServiceException(ErrorCode.REMOTE_DIRECTORY_SERVER_ERROR,
                      "HTTP Code is not OK, code=%s", result.getHttpCode());
          }
      }