[3.12] gh-139400: Make sure that parent parsers outlive their subparsers in `pyexpat` (GH-139403)#139609

ambv merged 2 commits intopython:3.12python/cpython:3.12from

hartwork:backport-6edb2dd-3.12hartwork/cpython:backport-6edb2dd-3.12Copy head branch name to clipboard