Many GitLab CI and Jenkins jobs are failing due to network problems
As [I reported in an unrelated issue](https://gitlab.torproject.org/tpo/tpa/tails-sysadmin/-/work_items/18271#note_3400144) there are intermittent network problems when trying to pull container images, but re-running seems to work.
Here are a few examples, note that the error messages are slightly different:
* [example](https://gitlab.tails.boum.org/tails/tails/-/jobs/278729) ([rerun](https://gitlab.tails.boum.org/tails/tails/-/jobs/278819))
* [another example](https://gitlab.tails.boum.org/tails/tails/-/jobs/278797) ([rerun](https://gitlab.tails.boum.org/tails/tails/-/jobs/278822))
* [an unrelated failure?](https://gitlab.tails.boum.org/tails/tails/-/jobs/279062) ([rerun](https://gitlab.tails.boum.org/tails/tails/-/jobs/279155))
Also, maybe this is yet another unrelated problem, but I am also spammed (570 emails since Friday) by some cron job failing on `apt.lizard`:
```
Subject: Cron <reprepro@apt> flock -n /var/lock/tails-update-reprepro-config /usr/local/bin/tails-update-reprepro-config '/srv/reprepro/tails.git' 'Tails' '/srv/reprepro'
Body:
fatal: unable to access 'https://gitlab.tails.boum.org/tails/tails.git/': GnuTLS, handshake failed: The TLS connection was non-properly terminated.
```
issue