[bug#74962] [PATCH] etc/guix-install.sh: Explicit shebang to use /usr/bin/env.

[Ludovic Courtès]

Maxim Cournoyer <maxim.cournoyer@gmail.com> skribis:

> Having an explicit shebang tells something useful: we depend on Bash.  Tools
> such as shellcheck make use of it.  The original technical reason for avoiding
> /usr/bin/env is no more (Guix System lacking it).
>
> * etc/guix-install.sh: Adjust shebang.  Remove conditional 'exec bash' further
> block below.
>
> Change-Id: I3c92a9e58fe11610dfbf74dbbd4b1ac8852abcf0

LGTM!