virsh: add sudo to an example

[Managor]

The only example I can test.

[FazleArefin]

Based on my extensive testing a few months ago, none of the virsh commands require sudo explicitly if the virtualization groups are setup properly (user should be a member of the group libvirt) and the correct URI for the user is set up as well.

This command should show you the URI being used:

virsh uri

I have attached my personal notes (not very tidy but very comprehensive) if you want to do a deep dive on your host.
qemu-kvm-installation.md

[Managor]

How I've been trying to document is by having as little outside configuration as possible. If the package that the command comes with doesn't set up the groups or the URI for the connection to work, it's better to document a command that works. In my case running sudo just makes virsh command work.