Tooling update

[SecondSkoll]

Updates Sphinx Stack to 2.0
Fixes some linting issues in content

QA instructions:

This update involves a lot of core code changes to the tooling which are in line with the tooling update (1.3 to 2.0) - and if issues are identified they should be raised in the parent project. It's up to you whether you want to go through all the changes or not. It's likely better to just check the preview build and ensure things you expect to work function correctly. Note: Due to this documentation set being served on the main URLs, 404 pages will not be configured currently due to a mismatch in path lengths.

[maxiberta]

Checked the build and it looks great! Thanks a lot.
A couple of comments/questions:

• The main tutorial page looks a bit broken - there are a few ::::{grid} 2 :::{grid-item-card} and ::::.
• Just a nit: some command line examples are in a fancy black terminal with a nice green prompt, while some other commands are just a bit indented with a clear background and mono font. It looks a bit inconsistent. Not clear if there's any distinction between them, or just maybe tech debt.

+1 anyway!

[SecondSkoll]

Tutorial index page should be fixed. There was an issue with some of the myst extensions not being loaded by default anymore.

The other issue is somewhat intended - in that the terminal extension is used to demonstrate input and output while the standard codeblocks are intended for one or the other.