nixosTests.packagekit: port to python

nixos/tests/packagekit.nix

···
-import ./make-test.nix ({ pkgs, ... }: {
+import ./make-test-python.nix ({ pkgs, ... }: {
   name = "packagekit";
   meta = with pkgs.stdenv.lib.maintainers; {
     maintainers = [ peterhoeg ];
···
   };
 
   testScript = ''
-    startAll;
+    start_all()
 
     # send a dbus message to activate the service
-    $machine->succeed("dbus-send --system --type=method_call --print-reply --dest=org.freedesktop.PackageKit /org/freedesktop/PackageKit org.freedesktop.DBus.Introspectable.Introspect");
+    machine.succeed(
+        "dbus-send --system --type=method_call --print-reply --dest=org.freedesktop.PackageKit /org/freedesktop/PackageKit org.freedesktop.DBus.Introspectable.Introspect"
+    )
 
     # so now it should be running
-    $machine->succeed("systemctl is-active packagekit.service");
+    machine.wait_for_unit("packagekit.service")
   '';
 })