callbackURL not work

[xujuvenile]

在config配置了callbackURL，实际未生效，

复现步骤：

1. git clone https://github.com/eggjs/examples.git

exports.passportYuque = {
  key: '$yours',
  secret: '$yours',
  callbackURL: "自定义回调地址",
  authorizationURL: "yuqueHost/oauth2/authorize",
  tokenURL: "$yuqueHost/oauth2/token",
  apiURL: "yuqueHost/api/v2",
};

----- update ------

1. config#callbackURL 没有找到引用的地方
2. egg-passport的mount方法，引用的是options，https://github.com/eggjs/egg-passport/blob/master/lib/passport.js#L58

也就是使用方法需为

  app.passport.mount('yuque', {
    callbackURL: "$你的回调地址",
  });