fix: children case-sensitivity and PR support

[SgtPooki]

• Children can be PRs now
• Correctly check for case-insensitive "children:"

fixes https://github.com/pln-planning-tools/Starmap/issues/360

demo: https://starmaps-git-360-bug-completion-rate-is-inva-152cdc-ipfs-ignite.vercel.app/roadmap/github.com/filecoin-station/roadmap/issues/1

[vercel[bot]]

The latest updates on your projects. Learn more about Vercel for Git ↗︎

Name	Status	Preview	Comments	Updated (UTC)
starmaps	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	May 9, 2023 9:05pm