bug#62045: 28.2; sed expression in install-etc does not work

[Eli Zaretskii]

> From: Ulrich Müller <ulm@gentoo.org>
> Date: Wed, 08 Mar 2023 08:53:07 +0100
> 
> The sed expressions in the install-etc make target don't match the
> strings in the two desktop files for emacsclient.
> 
> For emacsclient-mail.desktop, this was broken since its inception;
> for emacsclient.desktop, it is broken since commit cbf220bc31c0, where
> the shell wrapper was added.
> 
> A trivial patch is included below. Should it be installed on emacs-29,
> or on master?

On emacs-29, of course.

Thanks.