Security update for python, python-base, python-doc

This update for python, python-base, python-doc fixes the following issues Security fixes: - CVE-2026-1703: files may be extracted outside the installation directory when installing and extracting maliciously crafted wheel archives (bsc#1257599). - CVE-2026-3219: pip doesn't reject concatenated ZIP (bsc#1262429). - CVE-2026-3446: Base64 decoding stops at first padded quad by default (bsc#1261970). - CVE-2026-4786: Incomplete mitigation of %action expansion for command injection to webbrowser.open() (bsc#1262319). - CVE-2026-6019: BaseCookie.js_output() does not neutralize embedded characters (bsc#1262654). - CVE-2026-6100: Arbitrary code execution or information disclosure via use-after-free in decompression modules (bsc#1262098). - CVE-2026-6357: pip self-update functionality can import newly installed modules after wheel installation (bsc#1263442). Other fixes: - For SLE-12 use vendored libffi (bsc#1261652).