Move docs host once more

This new host only supports rsync-over-ssh, which means that we need to
use rsync-protocol syntax (`::` instead of `:` to separate host and
path), use a module name in front of the path (`www`) and explicitly
request ssh (`--rsh=ssh`).

skip-changelog, build infra change only.

.gitlab-ci.yml

@@ -44,10 +44,10 @@ variables:
     - RUSTDOCFLAGS="--cfg docsrs -D warnings" RUSTFLAGS="--cfg xmpprs_doc_build" cargo +nightly doc --no-deps -Zrustdoc-map --all-features
     - apt install -y rsync openssh-client
     - mkdir -p $HOME/.ssh
-    - echo -e "Host docs\n\tHostname ssh.docsxmpprs.sotecware.net\n\tPort 22\n\tUser docs\n\tStrictHostKeyChecking no" > $HOME/.ssh/config
+    - echo -e "Host docs\n\tHostname ssh.docsxmpprs-2025.sotecware.net\n\tPort 1312\n\tUser docs\n\tStrictHostKeyChecking no" > $HOME/.ssh/config
     - echo "$SECRET_DOCS_SSH_PRIVATE" > $HOME/.ssh/id_ed25519
     - chmod 400 $HOME/.ssh/id_ed25519
-    - rsync -av target/doc/ docs:$CI_DOC_TARGET
+    - rsync -av --rsh=ssh target/doc/ docs::www/$CI_DOC_TARGET
   rules:
     - if: $CI_PIPELINE_SOURCE == 'merge_request_event'
       variables: