Correctly handle --with-privileged-group

system-helper/org.freedesktop.Flatpak.rules.in

@@ -2,7 +2,7 @@ polkit.addRule(function(action, subject) {
     if ((action.id == "org.freedesktop.Flatpak.app-install" ||
          action.id == "org.freedesktop.Flatpak.runtime-install") &&
         subject.active == true && subject.local == true &&
-        subject.isInGroup("wheel")) {
+        subject.isInGroup("@privileged_group@")) {
             return polkit.Result.YES;
     }
 });