ui: utils: monitor_ceph_installed: avoid setting nodename to localhost

ui: utils: monitor_ceph_installed: avoid setting nodename to localhost

If a user is accessing the Ceph panel via Datacenter -> Ceph, then the
install & config wizard might be shown. The nodename that is passed to
the wizard  will decide the ID of the initial MON and MGR services.

Therefore, don't fall back to 'localhost' but the actual name of the
node to which we are connected to. The result will be that the first MON
and MGR will have the expected ID instead of 'localhost'.

Signed-off-by: Aaron Lauterer <a.lauterer@proxmox.com>