draft: fix invalid ASGI event handling

[joshua-auchincloss]

Summary

Please refer to #2171 for discussion points

• Refactor scope assertion to only check the event category (lifecycle, ws, http)

Checklist

• [Yes] I understand that this PR may be closed in case there was no previous discussion. (This doesn't apply to typos!)
• [Yes] I've added a test for each change that was introduced, and I tried as much as possible to make a single atomic change.
• [Yes] I've updated the documentation accordingly.
• [No] I've added a note on the docs/release-notes.md about my changes (changes on documentation or type annotations don't need this). - requested to maintainers to not conflict with active release notes