Known Issues document in SC hackathon guide is outdated.

[UtkarshBhardwaj007]

The know issues document linked in the polkadot-hubs-dev.md file is outdated. I created this document for a hackathon in May and this document has not ben maintained since. We should either update the document with the latest known issues or better yet, document it in our developer docs and link that.

[TriplEight]

Thanks for the issue. It would be great to have these docs updated and tested before the upcoming hackathon.
It's always better to keep documentation in a single, accessible and searchable place. I'm pro putting it into developer docs.