fix(vd): fix panic if pvc not found (#349)

fix panic if pvc not found
Signed-off-by: Yaroslav Borbat <86148689+yaroslavborbat@users.noreply.github.com>

images/virtualization-artifact/pkg/controller/vd/internal/validators/pvc_size_validator.go

@@ -148,8 +148,8 @@ func (v *PVCSizeValidator) ValidateUpdate(ctx context.Context, oldVD, newVD *vir
 		}
 		// When expanding pvc, the image located in the file system is not enlarged.
 		// This is why resizing disks in volume mode Filesystem is not supported.
-		if mode := pvc.Spec.VolumeMode; mode != nil &&
-			*mode == corev1.PersistentVolumeFilesystem &&
+		if pvc != nil && pvc.Spec.VolumeMode != nil &&
+			*pvc.Spec.VolumeMode == corev1.PersistentVolumeFilesystem &&
 			!oldSize.Equal(newSize) {
 			return nil, errors.New("resizing disks in volume mode Filesystem is not supported")
 		}