code: function preauth (app, heroku, secondFactor) {
    return heroku.request({
      method: 'PUT',
      path: `/apps/${app}/pre-authorizations`,
      headers: { 'Heroku-Two-Factor-Code': secondFactor }
    })
  }
docs: preauth will make an API call to preauth a user for an app
  this makes it so the user will not have to enter a 2fa code
  for the next few minutes on the specified app.
  
  You need this if your command is going to make multiple API calls
  since otherwise the secondFactor key would only work one time for
  yubikeys.
  
  @param {String} app the app to preauth against
  @param {Heroku} heroku a heroku api client
  @param {String} secondFactor a second factor code
  @return {Promise} A promise fulfilled when the preauth is complete