Based on information from https://endoflife.date/alpine, upstream support for alpine 3.20 will be ending on 2026-04-01. A PR should be created to remove this platform from our platform support document, CI, and packaging code.

• Remove platform from packaging/PLATFORM_SUPPORT.md
• Remove platform from .github/data/distros.yml
• Remove platform package builder from helper-images repo (if applicable).
• Verify any other platform support code that needs to be cleaned up.