Native QMessageBox on macOS doesn't show check box

The new macOS native QMessageBox in Qt 6.5 doesn't show the check box set with `setCheckBox`. If the check box isn't compatible with the native dialog, then I would expect it to automatically degrade to the non-native one. It's sort of gross to mix the two in the same app, but it would be better than not showing the check box at all. I also don't want to disable all native dialogs with `Qt::AA_DontUseNativeDialogs`, but a separate option to disable just native QMessageBox would work.