[Emacs] Only use .authinfo.gpg as an authsource

dotfiles/emacs.d/README.org

@@ -2200,6 +2200,14 @@ I don't use auto-complete at all, so I have set up a hook to automatically disab
   :config
   (setq straight-vc-git-auto-fast-forward t))
 #+END_SRC
+* auth-source
+#+begin_src emacs-lisp
+(use-package auth-source
+  :straight nil
+  :config
+  (progn
+    (setq auth-sources '("~/.authinfo.gpg"))))
+#+end_src
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