The authentication URL does not work anymore once you've got your Token.
It is no more : https://api.github.com/user?access_token=[token]
But : https://api.github.com/user with the token in the 'Authorization' header. The problem is that I could never make this work even following this documentation :
https://docs.github.com/en/developers/apps/authorizing-oauth-apps#2-users-are-redirected-back-to-your-site-by-github
Could you please fix the code on the repo since it renders basically chapters 5, 6 and 7 useless ?