style(cleanup): drop redundant comments from the power-off tasks

roles/cleanup/defaults/main.yml

@@ -3,7 +3,5 @@
 cleanup_verify_boot: true
 cleanup_boot_timeout: 300
 cleanup_remove_on_failure: true
-
-# How long to let the guest finish the shutdown started in shutdown.yml before forcing it off
 cleanup_poweroff_retries: 24
 cleanup_poweroff_delay: 5