Subject: guix build --keep-going (-k) not always honored

From: Jonathan Brielmaier <[email-masked]>
Date: Fri, 24 Feb 2023 23:15:43 +0100

I can confirm this bug.

```
$ guix describe
   guix ea2fa86
     Repository-URL: https://git.savannah.gnu.org/git/guix.git
     Branch: master
     Commit: ea2fa86f31a83195ac789a6d92bcaee8e53e4397
```

My example involves a bit more packages. Those who got back by `guix
refresh --list-dependent icu4c`.

```
$ guix build --keep-going [email-masked]
[email-masked] [email-masked] [email-masked] [email-masked]
[email-masked] [email-masked] [email-masked]
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```