weitere Korrekturen mit puppet-lint

manifests/unattended_upgrades.pp

 # unattended-upgrades konfigurieren
-class ubuntu_server::unattended_upgrades($automatic_reboot = false, $autoremove = true, $allowed_origins = ['${distro_id}:${distro_codename}-updates','LP-PPA-ubuntu-lxc-lxd-stable:${distro_codename}','Docker:ubuntu-${distro_codename}','Puppetlabs:${distro_codename}'], $package_blacklist = ['docker-engine']){
+class ubuntu_server::unattended_upgrades($automatic_reboot = false, $autoremove = true, $allowed_origins = ["\${distro_id}:\${distro_codename}-updates","LP-PPA-ubuntu-lxc-lxd-stable:\${distro_codename}","Docker:ubuntu-\${distro_codename}","Puppetlabs:\${distro_codename}"], $package_blacklist = ['docker-engine']){
 
     File{
         owner => root,