suppress unauthorized error from status query for VM.Console only user

suppress unauthorized error from status query for VM.Console only user

We now query the guest status before starting the console to provide
a start button if it's not yet running, but that requires VM.Audit
privileges, so more than just VM.Console on the guest.

So, ignore a `403 Forbidden` response, as that just means we cannot
query the VM info to see if it's running, rather just continue
connecting.

See: https://forum.proxmox.com/threads/116176/
Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
 [ T: reworked commit message ]
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>