pinning jupyter-book

[edublancas]

Describe your changes

Issue ticket number and link

Closes #x

Checklist before requesting a review

• [ ] I have performed a self-review of my code
• [ ] I have added thorough tests (when necessary).
• [ ] I have added the right documentation in the docstring and changelog (when needed)

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:books: Documentation preview :books:: https://ploomber-engine--56.org.readthedocs.build/en/56/