Textbook cannot be built with OCaml 5

[clarksmr]

We depend on Ocaml-Jupyter and it does not support OCaml 5 since 2023.

[zhelih]

Hi, we have a version of OCaml Jupyter working with OCaml 5.2 or newer, if you are willing to try. The plan is to get a PR to the upstream shortly.

https://github.com/zhelih/ocaml-jupyter/tree/ocaml_5