create host from template: error Failed to create a compute XXX (Proxmox) instance YYY: undefined method `volid' for nil:NilClass

[betonmoewe]

Describe the bug
I am trying to create a new host in my ProxMox cluster from an existing tremplate using Foreman / Katello. Unfortunately without success ... the deployment cancels with the following error message:
"Failed to create a compute sfravm-..... (Proxmox) instance sandy-kilborne...: undefined method `volid' for nil:NilClass
Unfortunately I have no idea where this comes from

To Reproduce
Steps to reproduce the behavior:

1. go to 'create host'
2. enter all needed information
3. under os selecting "image based" and selecting the source image
4. click "submit"
   -> error "unable to save"

Expected behavior
Foreman should create a new virtual machine

Screenshots
If applicable, add screenshots to help explain your problem.

Information:

• Katello: 4.12.0
• Foreman: 3,10.0
• ProxMox plugin: 0.15.0
• ProxMox: 8.2.2

Just tested with 0.15.1: Failed to create a compute sfravm-... (Proxmox) instance sheri-kroner....: ERF42-8301 [Foreman::Exception]: Failed to create file user-data: bash: -c: line 14: syntax error near unexpected token (' bash: -c: line 14: sudo: ['ALL=(ALL) ALL']'