Description of problem:

Currently the image based provisioning in foreman_kubevirt is utilizing a containerDisk, which is an ephemeral, shared volume that can be used to boot machines.
However, image based provisioning in Foreman/Satellite is usually a "golden image" style provisioning: a given disk image is copied and the new, writable, copy is used to boot the VM.
To achieve this workflow, a DataVolume needs to be created using a DataVolumeTemplate with its "DataSource" pointing at an existing DataVolume

spec:
  dataVolumeTemplates:
    - apiVersion: cdi.kubevirt.io/v1beta1
      kind: DataVolume
      metadata:
        creationTimestamp: null
        name: centos-stream9-amd64-chocolate-halibut-57
      spec:
        sourceRef:
          kind: DataSource
          name: centos-stream9-amd64
          namespace: openshift-virtualization-os-images
        storage:
          resources:
            requests:
              storage: 30Gi
  runStrategy: RerunOnFailure

How reproducible:

Always

Is this issue a regression from an earlier version:

Steps to Reproduce:

1. Create a host under OCP-V
2. Select an image
3. Click build

Actual behavior:

The host will not be created and will report errors around improper disk definition.
Or, if the host creation succeeds (as the error is just a length check failing, so it can succeed), you get a system with a wrong rootdisk type.

Expected behavior:

A host is created using the image as a template. And the resulting host disk is not ephemeral.

The user is enabled to configure the size/storage class of the created volume