CI runner failure

[hannesm]

the output I observe is:

fatal: unable to access 'https://github.com/ocaml/opam-repository/': Could not resolve host: github.com
"/usr/bin/env" "bash" "-c" "cd ~/opam-repository && (git cat-file -e f9d23e5cb169337cdf0aac6321e4ec46f6f64a74 || git fetch origin master) && git reset -q --hard f9d23e5cb169337cdf0aac6321e4ec46f6f64a74 && git log --no-decorate -n1 --oneline && opam update -u" failed with exit status 128
2025-08-22 11:47.17: Job failed: Failed: Build failed

source:
https://ocaml.ci.dev/github/mirage/charrua/commit/56d70bbfa1621aa6f46b221f35d137e68b412e9d/variant/debian-12-4.14%2Bflambda_opam-2.4
https://ocaml.ci.dev/github/mirage/charrua/commit/56d70bbfa1621aa6f46b221f35d137e68b412e9d/variant/ubuntu-22.04-5.3_opam-2.4