Provision to assign disk offering(s) for volumes(s) when migrate VM with volumes

### problem

Currently, Migrate VM with volume(s) bypasses the service and disk offerings of the volumes, as the target pools for migration are specified and volumes can be moved between shared to local and local to shared pools without any offering change. The subsequent operations on these volumes were impacted due to disk offering and pool type mismatch.

There should be provision to admin/operation, to assign disk offering(s) for volumes(s) with proper checks, when migrate VM with volumes (mainly when change in pool type - shared to local, local to shared). Similar provision was already there for Migrate volume, and it prompts to change the disk offering.

### versions

ACS 4.20.x , KVM Hypervisor, NFS / Local Storage.

### The steps to reproduce the bug

1. Deploy a VM with ROOT and DATA volumes on Local storage.
2. Migrate VM with volumes to NFS (Shared) storage - the Disk Offerings still point to Local storage offering.

### What to do about it?

Allow operator to assign disk offering(s) for volumes(s) when migrate VM with volumes, or auto assign the suitable offering.

Inizia confrontando il flusso Migrate volume esistente, che richiede un disk offering, con il flusso Migrate VM with volumes descritto nell’issue. Riproduci la migrazione dallo storage locale a NFS e verifica che il comportamento completato consenta di assegnare disk offerings adatti con controlli oppure li assegni automaticamente senza una mancata corrispondenza del tipo di pool.

Scritto dal modello di indicizzazione a partire dal testo della issue.