nixos/test: Port test driver to python

Thanks @blitz and @jtraue for help with implementing machine methods

nixos/tests/make-test-python.nix

@@ -0,0 +1,9 @@
+f: {
+  system ? builtins.currentSystem,
+  pkgs ? import ../.. { inherit system; config = {}; },
+  ...
+} @ args:
+
+with import ../lib/testing-python.nix { inherit system pkgs; };
+
+makeTest (if pkgs.lib.isFunction f then f (args // { inherit pkgs; inherit (pkgs) lib; }) else f)