TEST: updates to sphinxcontrib-tojupyter

[mmcky]

I would like to test updates made in QuantEcon/sphinxcontrib-jupyter#343 in this PR.

We can update our environment.yml file to use

git+https://copilot/https://github.com/QuantEcon/sphinxcontrib-jupyter@fix-342

We can then compare the notebooks from this step in ci.yml

lecture-python-programming.myst/.github/workflows/ci.yml

Line 44 in dd8d502

- name: Build Download Notebooks (sphinx-tojupyter)

with outputs located in _build/jupyter/*.ipynb

and cross compare them with the last published notebooks in https://github.com/quantecon/lecture-python-programming.notebooks

[mmcky]

Using an incorrect extension. We should update the sphinx-tojupyter