cmd/ssh-auth-none-demo: put the hostname in the package doc

188.166.70.128 port 2222 for now. Some hostname later maybe.

Change-Id: I9c329410035221ed6cdff7a482727d30b77eea8b
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>

cmd/ssh-auth-none-demo/ssh-auth-none-demo.go

@@ -3,9 +3,10 @@
 // license that can be found in the LICENSE file.
 
 // ssh-auth-none-demo is a demo SSH server that's meant to run on the
-// public internet and highlight the unique parts of the Tailscale SSH
-// server so SSH client authors can hit it easily and fix their SSH
-// clients without needing to set up Tailscale and Tailscale SSH.
+// public internet (at 188.166.70.128 port 2222) and
+// highlight the unique parts of the Tailscale SSH server so SSH
+// client authors can hit it easily and fix their SSH clients without
+// needing to set up Tailscale and Tailscale SSH.
 package main
 
 import (