Upgrade sphinx-tojupyter to 0.4.0

[mmcky]

This PR upgrades sphinx-tojupyter from version 0.3.1 to 0.4.0 in the environment.yml file.

Changes:

• Updated sphinx-tojupyter dependency from 0.3.1 to 0.4.0

Testing:
The CI workflow will validate that the build completes successfully with the new version.

[mmcky]

@HumphreyYang once this builds would you mind being a second set of eyes on:

• html for McCall model with separation (lecture with glue)
• download the notebook of that lecture and check locally for the included glue figures
• verify the latex for that lecture with included glue figures
• collab will only work once we publish and updated notebooks are pushed to notebooks repo

[HumphreyYang]

@HumphreyYang once this builds would you mind being a second set of eyes on:

Sure I will update once I tick off all the boxes.

[github-actions]

📖 Netlify Preview Ready!

Preview URL: https://pr-702--sunny-cactus-210e3e.netlify.app (e979d50)

[HumphreyYang]

• verify the latex for that lecture with included glue figures

Hi @mmcky the first two items look great! For the latex, I think the figure is not fixed at the position.

We might need to tag is using [h!]?

[mmcky]

thanks @HumphreyYang that will need to be addressed via _config.yml or sphinx-jupyterbook-latex -- so I think we can merge this.

[HumphreyYang]

Many thanks @mmcky, I agree!