We don't want these comments to be added to docs/ssh-known_hosts.txt.

From OpenSSH 9.8 release notes [1]:

 * ssh-keyscan(1): this tool previously emitted comment lines
   containing the hostname and SSH protocol banner to standard error.
   This release now emits them to standard output, but adds a new
   "-q" flag to silence them altogether.

[1] https://www.openssh.com/txt/release-9.8

gitlab.archlinux.org's host SSH daemon now listens on port 2222. Adjust
the sync-ssh-hostkeys task to take this into account. Port 22 is for GL.

ansible-lint 6.5.0 complains about:

  name: All names should start with an
        uppercase letter. (name[casing])

The glibc 2.35-6 package ships with the C.UTF-8 locale included which
means there is now a usable UTF-8 locale available by default.

en_US.UTF-8 will still be generated because PostgreSQL clusters are
created with that locale. Migrating the clusters to C.UTF-8 is
possible, but that requires dumping and recreating them.

These are used to signal the start of the document in a stream of many
documents. As Ansible only supports one YAML document per file this is
unnecessary. About a third of our YAML documents already lacked these.

Do the same for the hostkeys/known_hosts templates and disable fact
gathering.

These are managed services and Ansible doesn't run on them. It got
boring writing 'all,!rsync_net,!hetzner_storageboxes' in playbooks
and ad-hoc commands, so remove these borg hosts from our inventory.

Change docs/ssh-known_hosts.txt to be partially managed by Ansible, so
custom entries can be added to the top of the file. Use the new format
to write down the host keys of our two borg hosts.

New username; separate and longer account manager + storage passwords.

Also, have to use --remote-path=borg1 when interacting with rsync.net.

yaml: truthy value should be one of [false, true] (truthy)
yaml: wrong indentation: expected 4 but found 2 (indentation)
yaml: too few spaces before comment (comments)
yaml: missing starting space in comment (comments)
yaml: too many blank lines (1 > 0) (empty-lines)
yaml: too many spaces after colon (colons)
yaml: comment not indented like content (comments-indentation)
yaml: no new line character at the end of file (new-line-at-end-of-file)
load-failure: Failed to load or parse file
parser-error: couldn't resolve module/action 'hosts'. This often indicates a misspelling, missing collection, or incorrect module path.

Just in case, locales are complicated...

Fixes #196

We forget doing this too often. :(

As repro3 is Ubuntu and it's default shell is dash, set -o pipefail is
not supported.

Signed-off-by: Florian Pritz <bluewind@xinu.at>