The community-maintained Debian repository linked in the Linux install
docs moved from `debian.griffo.io` to `deb.griffo.io` to comply with the
[Debian trademark policy](https://www.debian.org/trademark) (Debian
trademarks may not be used in domain names). Same repository, packages,
and signing key; the old domain serves permanent redirects, so existing
links keep working — this just points the docs at the canonical URL.

I maintain the repository in question.

Release Notes:

- N/A