Should use access token to retrieve Google account ID (email)

[dixonsiu]

Solution (Reference)

1. Add the following scope to the authorization request.
   "https://www.googleapis.com/auth/userinfo.email"
2. After the reqest returns an access token, send a GET request using the following endpoint.
   "https://www.googleapis.com/userinfo/email?alt=json"

3. Response sample:

   {
       "data":{
           "email": "dixon.siu@gmail.com",
           "isVerified": true
      }
   }