Include notebook in testing

[lkct]

As indicated in #153, we can forget to update the notebook when the API changes.

It should be better to have a unit test to guarantee that the notebook can still run after some change.

[loreloc]

As a long term view for the repository, perhaps move notebooks to another repository.
The reason is that we do not need versioning for the majority of the bits stored in a notebook (e.g., images).

[loreloc]

Perhaps use this to run the notebook for the test.

https://stackoverflow.com/questions/67811531/how-can-i-execute-a-ipynb-notebook-file-in-a-python-script

[loreloc]

Might be worth looking into https://github.com/chrisjsewell/pytest-notebook