Add jupyter notebook actions

[thijshberg]

Jupyter notebook steps are part of cacao, and it makes sense to support them.

This might be useful for playbook conversion, as other formats are either playbooks directly or use python code, and we could use jupyter notebook steps to apply a meaningful conversion.

[thijshberg]

There are two sensible options to achieve this support. Both have been explored in the feature branch to some extent.

Remote server

We have a separate deployment set up to run jupyter notebooks over SSH. That is, we send a playbook over SSH and retrieve all its output.

This has the benefit that it is much easier to set up than the alternative. It also keeps the soarca process clean in that it does not spawn any new processes/containers.

The downside is that we run untrusted arbitrary notebooks in our container, which is bad.

Container spawning

We make a container image set up for running jupyter notebooks, and for each notebook we execute this image only running the notebook (using containerd).

This has the benefit that containerization of the notebook is guaranteed.

The downside is that it is very tricky to get right (lots of hard-to-debug errors with no clear origin), and depends on the underlying system for spawning containers (with different errors). It also requires extra setup in adding a zipped container and extra container fiddling for deployments (if it is doable at all to spawn containers from within a container).