bug#47727: halt system test is broken

[Mathieu Othacehe]

Hello,

The "halt" test is broken, see:
https://ci.guix.gnu.org/build/166624/details.

It fails to read the "root@komputilo" string using Ocrad. I captured an
attached screenshot that is used for the OCR detection.

Running manually "ocrad -i -s 10 tty1.ppm" gives no result. However
running the same command with a scale to 3 works:

--8<---------------cut here---------------start------------->8---
mathieu@meije ~/guix [env]$ ocrad -i -s 3 tty1.ppm  
This is the GNU sVstem. welcome.
komputilo login: root
This is the GNU operating sVstem, welcome!

root@komputilo w# _
--8<---------------cut here---------------end--------------->8---

I wonder if this regression comes from Ocrad itself or from the input
Qemu screeshot.

Thanks,

Mathieu

tty1.ppm
Description: image/portable-pixmap