[project] Setup branch to use `sphinx-book-theme` developed by EBP

[mmcky]

Now that @najuzilu has migrated lecture-python-programming to myst we have a direct comparison of the rst and myst parsers. Given both parsers use docutils we can use this project as a test case for finding possible edge cases.

By enabling sphinx-book-theme in a branch of this repository we can build and compare html outputs.

Note: additional features such as glue in ebp will need to be ignored.

[mmcky]

This is now done in branch enable-sphinx-book-theme but it won't be as useful as initially thought without the executed outputs etc. We can't use the theme with sphinxcontrib-jupyter as it is not configured for that. We can compare html builder outputs but it is missing elements such as logo's etc.

• fix missing logo images