www/node20: Update to 20.20.2
Changes: https://github.com/nodejs/node/releases
https://github.com/nodejs/node/blob/main/doc/changelogs/CHANGELOG_V20.md
Security: CVE-2026-21637, CVE-2026-21710, CVE-2026-21713, CVE-2026-21714, CVE-2026-21715, CVE-2026-21716, CVE-2026-21717