Matt McKay

- [x] re-enable build cache - [x] open an issue to update pip install from `main` branch of `interpolation` repo to pypi once released

- [x] reverted to install `interpolation` from `pypi` which is currently `2.2.6`

@HumphreyYang would you have time to investigate what these `warnings` mean? It appears to be issued due to `python=3.11` https://discourse.jupyter.org/t/debugger-warning-it-seems-that-frozen-modules-are-being-used-python-3-11-0/16544 It isn't stopping execution so I am going to go...

This is still being actively discussed in forums so will leave it open but I don;'t think this is an issue we will need to resolve.

@jstac we would need to specify the `conda-forge` channel for the `interpolation` package so I don't really see a lot of benefit in making the change. What do you think?

- [x] wait for https://github.com/QuantEcon/lecture-python-intro/pull/340 to be merged.

@HumphreyYang are you happy for this to be merged? It looks like the requirements are now fulfilled.

thanks @HumphreyYang

@DrDrij it looks like we need floating `equation numbers` for `quantecon-book-theme` to support wide equations?

@DrDrij any ideas on this one? Let me know when you might have some time to look at this. Thanks.