Fixes #33871 - drop foreman-xen plugin
See https://community.theforeman.org/t/foreman-xen-plugin-is-unmaintained-what-should-be-done/21688
Fixes #33871 - drop foreman-xen plugin
See https://community.theforeman.org/t/foreman-xen-plugin-is-unmaintained-what-should-be-done/21688