Node Explorer: Attach VS Code fails if Tailscale SSH requires an additional check

[tendstofortytwo]

Sometimes, Tailscale SSH will require the user to go through an additional auth flow before logging in. If this auth flow is encountered when the user clicks "Attach VS Code", the VSCode remote SSH mechanism doesn't recognize Tailscale's prompt to click an extra link, and hangs until timeout.

This can be fixed by us running a simple ssh <machine> echo test sort of command, catching the auth link if it appears, and opening it for the user, before passing the connection details to VSCode.