bug#61973: M-x gdb ends up with infinite prompts before starting the process

[Dmitry Gutov]

1. Run compiled 'emacs' from 'src'.
2. M-x gdb
3. Answer prompt: Run gdb (like this): gdb -i=mi ./emacs
4. See this prompt repeated indefinitely, no matter what I answer:

This GDB supports auto-downloading debuginfo from the following URLs:
https://debuginfod.ubuntu.com
Enable debuginfod for this session? (y or [n]) Please answer y or [n].

(Emacs 29, more or less latest.)