home-manager: use short -f instead of --fqdn

[gauravjuvekar]

Description

MacOS doesn't support the long-style --fqdn option to hostname that
was added by 1b58925.

Switch to short style -f that should be supported on every platform.

Checklist

• Change is backwards compatible.

• Code formatted with ./format.

• Code tested through nix-shell --pure tests -A run.all or nix develop --ignore-environment .#all using Flakes.

• Test cases updated/added. See example.

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Maintainer CC

[rycee]

Thanks for the quick fix. Merged now 🙂

[ilyagr]

Thank you very much!

Just FYI, on Mac OS, hostname -f seems to be the same as hostname. See e.g. https://man.freebsd.org/cgi/man.cgi?hostname(1) .