bug#74250: emacs-guix: guix-pull invalid input error

[Christopher Howard]

After cleaning up my profiles, and some other troubleshooting, I eventually 
realized that the failure can be bypassed by setting guix-repl-use-server to 
nil, i.e., disabling emacs-guix from using the additional Internal REPL 
(#<buffer *Guix\ Internal\ REPL*>).

The Internal REPL gave me trouble in another bug as well. I'll need to try to 
get a better understanding of how the magic of the Internal REPL works and how 
it could be messing this up.

-- 
Christopher Howard