Bump jupyter-book version to 2.0

Jupyter Book 2 raises an EISDIR error during the build in our CI because the build command changed its behavior to explicitly require paths. If we want to bump to Jupyter Book 2, we'll have to:
- [ ] Modify `environment-dev.yml` and `requirements-dev.txt` to require `jupyter-book >= 2.0`
- [ ] Modify the `Makefile` to explicitly require paths
- [ ] Modify the netlify deploy in `jupyter-book-pr-preview.yml` to match the new `_build` path
- [ ] Follow the [How to upgrade](https://jupyterbook.org/stable/resources/upgrade/#how-to-upgrade) instructions to automatically create a `myst.yml` file with the configuration
- [ ] Debug :
- [ ] the `toctree` to match previous config
- [ ] slides in video lessons not showing
- [ ] possibly other bugs