Description of problem:
Common Templates with Same OS may have different SRC_PVC_NAME name, The UI should handle this cases gracefully, or show an error.

Componenets affected:
a - Create VM Wizard:
- When choosing an OS a new disk is created using the latest template available for this OS
- After choosing a flavour or workload, the template used may change, and the disk that was created change.

b - PVC upload and delete:
- When a user choose to upload a disk image for an OS the form uses the SRC_PVC_NAME from the latests template available for that OS, but the user may want to use a flavour/workload that is only available in an older version that uses an older version of the disk0image name.

Version-Release number of selected component (if applicable):


How reproducible:


Steps to Reproduce:
1. change or delete the SRC_PVC_NAME and SRC_PVC_NAMESPACE in a common template for some OS and flavor.
2. go to the wizard and choose this OS.
3. check that the disk created for you use the correct PVC with correct name and name-space.
4. continue with the form and choose the flavour of the template you updated.
5. check the disk image in the   
6. check that the disk created for you use the correct PVC with correct name and name-space.

Actual results:
- the PVC name in step 6 may change to match the new template
- the PVC name in step 6 may not change to match the new template

in both cases user is not aware that the disk image was changed, or that it does not match the new template.

Expected results:
the user get some notice that the disk image is:
- changed from the disk image he sqw in the OS input step.
- or the disk image now does not match the disk image from the template.

Additional info:
On a well maintained system Common Templates with Same OS must have same SRC_PVC_NAME and SRC_PVC_NAMESPACE.