nixos/tests/hibernate: Fix netcat flags

I'm not sure why 024b5019 used -q 0
because even netcat-openbsd has the -N flag which IMO is the better way
to shutdown the socket on EOF.

Our default netcat implementation has changed once again[1] in
3c3b8223 and we're now using LibreSSL's
implementation, which doesn't have a -q flag.

See https://github.com/NixOS/nixpkgs/pull/39634 for the pull request
introducing the switch.

[1]: https://github.com/NixOS/nixpkgs/pull/19982



Signed-off-by: aszlig <aszlig@nix.build>
Cc: @matthewbauer, @dtzWill, @Mic92