gh-80448: argparse: Fix IndexError on store_true action (#15656)

Co-authored-by: Rémi Lapeyre <remi.lapeyre@henki.fr>
Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>
Co-authored-by: Shantanu <12621235+hauntsaninja@users.noreply.github.com>
3 files changed