docs: ulwazi theme test, build failures

*Please describe the question or issue you're facing with "Test the Ulwazi theme - Documentation starter pack documentation".*

* I had some problems with the code blocks missing commas (in various places), so the docs refused to build until they were all added
* Similarly with nbsps, which I had to manually reindent
* There's a conflict in the dependencies where in the config file you're calling for the sphinx-terminal extension to be invoked, but it's not included in the list of dependencies in requirements.txt (I noticed this because I have it turned off by default)
* I also get an error on the "sphinx_modern_pdf_style" extension, which is also not included in requirements.txt
* The build also gives me the following errors:
* `WARNING: unsupported theme option 'source_edit_link' given` (might be related to my own config)
* `WARNING: Skipping build combination due to build error`
* ```
Theme error:
An error happened in rendering the page contributing/contrib-types.
Reason: TemplateNotFound("'furo/page.html' not found in ['/home/sally/src/test-repos/test-ulwazi/docs/.sphinx/_templates/', '/home/sally/src/test-repos/test-ulwazi/docs/.sphinx/venv/lib/python3.10/site-packages/ulwazi/theme/ulwazi', '/home/sally/src/test-repos/test-ulwazi/docs/.sphinx/venv/lib/python3.10/site-packages/sphinx_basic_ng/theme/basic-ng', '/home/sally/src/test-repos/test-ulwazi/docs/.sphinx/venv/lib/python3.10/site-packages/sphinx/themes/basic']")
Sphinx exited with exit code: 2
```
* Not sure where furo is being called from, since it wasn't explicitly set in my config before

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*Reported from: https://canonical-starter-pack.readthedocs-hosted.com/stable/how-to/test-ulwazi-theme/*