bug#44650: Do not suggest `guix pull --news' after first pull

[pelzflorian (Florian Pelz)]

After doing a `guix pull` on the new VM image
<https://alpha.gnu.org/gnu/guix/guix-system-vm-image-1.2.0rc1.x86_64-linux.xz>,
the following is displayed:

> hint: Run `guix pull --news' to read all the news.
> 
> hint: After setting `PATH', run `hash guix' to make sure your shell refers to 
> `/home/guest/.config/guix/current/bin/guix'.

The former `guix pull --news` is without effect (it is the very first
time I did a `guix pull`).  It is a no-op.  Users should not get the
suggestion to run `guix pull --news`.


Within (guix scripts pull)’ build-and-install procedure, the value of
(display-channel-news-headlines profile) is <unspecified>.

The attached patch changes it to return #f.  I have verified running
`guix pull --news' is not suggested anymore with it (although I have
not tested if news are still displayed).

It would perhaps be nicer if the news since version 1.2.0 were
displayed, but I do not know how to make it so.  I guess since the
original guix package must come from the guix package in (gnu packages
package-management), it is impossible to determine the version from
which news should be computed.

Regards,
Florian

0001-pull-Do-not-suggest-running-guix-pull-news-on-the-fi.patch
Description: Text document