doc: AsciiDoctor for Ubuntu/Debian

Adds `asciidoctor` for Ubuntu 22/24 and Debian Trixie as required by the
asciidoc PR.

Related-to: cockpit-project/cockpit#21515
Signed-off-by: Freya Gustavsson <[email protected]>

Author: Venefilyn

images/scripts/debian.setup

@@ -274,6 +274,8 @@ cat <<EOS >> /tmp/pbuilder_script
 $(/usr/lib/pbuilder/pbuilder-satisfydepends-classic --control /tmp/out/tools/debian/control --force-version --echo|grep apt-get)
 # TEMP: until these make it into cockpit.git
 apt-get -y install esbuild node-argparse node-gettext-parser node-mime-db node-react node-react-dom
+# TEMP: until asciidoc migration is into cockpit.git.
+apt-get -y install asciidoctor
 EOS
 
 pbuilder execute --save-after-exec -- /tmp/pbuilder_script