bug#65027: 30.0.50; [PATCH] Document .elpaignore behavior in the Emacs Lisp manual

[Eli Zaretskii]

> From: Stefan Kangas <stefankangas@gmail.com>
> Date: Sat, 27 Jan 2024 21:49:23 -0800
> Cc: philipk@posteo.net, corwin@bru.st, monnier@iro.umontreal.ca, 
>       info@protesilaos.com, 65027@debbugs.gnu.org
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > Thanks, I fixed it slightly.
> 
> I cherry-picked it to emacs-29, so perhaps the fix should be
> cherry-picked there too.  It seemed more natural for a documentation fix
> to be on the release branch.

I wasn't sure the description is valid for Emacs 29.  If it is, then
yes, please cherry-pick the fix as well.