I have a machine with a VirtIO disk. At the moment it has a disc of 1 tb, but I am wasting a lot of space. What I want is to change it for a smaller disk. But I have no idea how to do it. Someone knows some guide or some step to be able to do this. Since proxmox gives me the option to increase the disk but not decrease, and backups take me a long time, so I would like to decrease the disk.