Feature: Support GitHub discussions

Hi @simonw I've been a happy user of this tool.  Thank you for writing it and sharing it.

I wanted to suggest a feature request to support  Discussions.  For example the VisiData project has discussions https://github.com/saulpw/visidata/discussions , and it would be useful if there was a way to pull that data into the database.

However, I'm not offering a pull request.