fix(vm): no IP address detection when VM contains bridges (#493)

When the VM contains at least one bridge, the main interface (e.g.
`eth0`) is left without an IP address because that's how networks
usually work.

The code that queries the VM's IP addresses (through the guest agent),
loops all available interfaces to find one. The existing code though
would prematurely exit the loop if the interface it was checking had no IP
address assigned. Like the aforementioned `eth0`, when it is controlled
by a bridge.

This patch fixes this problem by not exiting the loop, instead just continuing
to the next interface.

proxmox/nodes/vms/vms.go

@@ -445,7 +445,7 @@ func (c *Client) WaitForNetworkInterfacesFromVMAgent(
 
 						if nic.IPAddresses == nil ||
 							(nic.IPAddresses != nil && len(*nic.IPAddresses) == 0) {
-							break
+							continue
 						}
 
 						for _, addr := range *nic.IPAddresses {