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

roles/cleanup/tasks/proxmox.yml

@@ -8,10 +8,6 @@
     community.proxmox.proxmox_kvm: "{{ _proxmox_auth_node }}"
     community.proxmox.proxmox_vm_info: "{{ _proxmox_auth_node }}"
   block:
-    # shutdown.yml halts the guest without waiting for it, so stopping a VM Proxmox has
-    # already stopped errors out. Wait the shutdown out, and force off only a guest that
-    # ignored it. The disks come off afterwards, so they are never detached from a
-    # running VM.
     - name: Wait for the installer environment to power off
       community.proxmox.proxmox_vm_info:
         vmid: "{{ system_cfg.id }}"