Better integration with selected online Jupyter notebook service

[adamjanovsky]

Up to date, we've been integrating sec-certs with mybinder.org. That service unfortunately failed us during Estonian demo, for the sake of which we used deepnote.com.

We should revisit the problem and better integrate our tool with a selected online Jupyter notebook service. The work on this issue should:

• Analyze possible solutions (binder, google collab, deepnote, github dev). We'd like to have something with strong CPU, for free, and without login (ideally, what a list of requirements 😆 )
• Integrate all existing notebooks with the selected service
• All notebooks should be revisited. We shall check if we can run them out of the box from the top to the bottom, possibly with changing one line of code (local dataset instantiation -> remote instantiation)
• The solution should be advertised from GitHub readme, we should give buttons that lead to the notebooks
• The solution should be advertised from the documentation. From inspecting notebook, it should be possible to click to the online solution.