[AUTOPATCHER-CORE] Upgrade python-mistune to 3.2.1 CVE-2026-33079 [HIGH]

[CBL-Mariner-Bot]

[AUTOPATCHER-CORE] Upgrade python-mistune to 3.2.1 CVE-2026-33079
Upgrade pipeline run -> https://dev.azure.com/mariner-org/mariner/_build/results?buildId=1115023&view=results
Buddy Build

[Kanishk-Bansal]

No breaking changes are documented in the changelog between v3.0.2 and v3.2.1 at lepture/mistune@v3.0.2...v3.2.1.

All entries are bug fixes, security/escaping improvements, and additive changes (no "Breaking change" markers, which the maintainer did use explicitly for earlier 3.0.0 release candidates).

Highlights across the range (v3.1.0 → v3.2.1):

• v3.2.1 (May 2026) — Mostly security/escaping fixes:
  • Escape link in render_toc_ul, escape text in math plugin, escape heading ID, escape class attribute for admonition/image directives
  • Fix LINK_TITLE_RE to prevent DoS
  • Remove double-encoding of image alt text
  • Fix width/height attribute for image directive
• v3.2.0 — Python 3.14 support; footnotes plugin fixes; ref links in TOC fix
• v3.1.4 — Fenced directive break rule in list parser; unicode whitespace fix in ATX headings
• v3.1.3 — Python 3.12/3.13 support
• v3.1.2 — footnotes plugin fix for AST renderer
• v3.1.1 — render_toc_ul empty iterable fix; ruby plugin regex/HTML fixes
• v3.1.0 — Only HTML-escape URLs when rendering to HTML; block_quote prefix on empty lines