bug#72992: 29.4; towards xoauth2 support in Emacs

Friendly ping for feedback. -- Xiyue Deng

bug#72358: 29.4; oauth2.el improvements

.html -- Xiyue Deng

bug#72992: 29.4; towards xoauth2 support in Emacs

Now that bug#72358 is done, as promised, I'm posting my plugin for auth-sources that enables oauth2 handling which you can find on Gitlab[1] (also attached). As the current approach tries to override some existing handling in auth-source, I would like to gather some comments on how to properly int