Document this action in other repos

[Ostrzyciel]

We should document that this action exists in here: https://github.com/Jelly-RDF/cli/blob/main/README.md

And here: https://jelly-rdf.github.io/dev/use-cases/

We could later restructure the main Jelly docs a bit to emphasize ready-made tools more, instead of libraries. This would include stuff like jelly-cli, this action, and RMLMapper. Make a task for this in here: https://github.com/Jelly-RDF/jelly-protobuf