handleLoginAttempt(loginSuccessful) {
    if (!this._config.accountLockout) {
      return Promise.resolve();
    }
    return this._notLocked().then(() => {
      if (loginSuccessful) {
        return this._setFailedLoginCount(0);
      } else {
        return this._handleFailedLoginAttempt();
      }
    });
  }
handle login attempt if the Account Lockout Policy is enabled