code: public void setDefaultTransactionTimeout(int timeoutSecs) throws Exception {
          final Address address = Address.root().add(SUBSYSTEM, TRANSACTIONS);
          final ModelNode req = createWriteAttributeRequest("default-timeout", String.valueOf(timeoutSecs), address);
          final ModelNode response = execute(req);
  
          if (!isSuccess(response)) {
              throw new FailureException(response);
          }
          return;
      }
docs: Sets the default transaction timeout.
  @param timeoutSecs the new default transaction timeout, in seconds.
  @throws Exception any error