feat: Upgrade to Jupyter Book v2

[matthewfeickert]

• Migrate to Jupyter Book v2.
  • book/_config.yml and book/_toc.yml are combined into book/myst.yml.
  • Update Pixi commands to use cwd to be in the correct directory tree for myst.
• Upgrade Pixi workspace.
  • Add insecure run-post-link-scripts for ROOT.
  • Update Pixi 'start' task.

[matthewfeickert]

@kratsg I'm going to take this failing CI as an opportunity to just migrate things to Jupyter Book v2

[matthewfeickert]

Things that existed in Jupyter Book v0

pyhf-tutorial/pixi.toml

Line 39 in 6b4c464

jupyter-book = "0.15.1.*"

that I'm not sure how to do now:

• Set execution timeouts

pyhf-tutorial/book/_config.yml

Lines 7 to 8 in 6b4c464

	execute:
	timeout: 210 # seconds

• Set launch buttons for Binder and other tools

pyhf-tutorial/book/_config.yml

Lines 23 to 27 in 6b4c464

	# Launch button settings
	launch_buttons:
	notebook_interface: jupyterlab
	binderhub_url: https://mybinder.org
	colab_url: https://colab.research.google.com

[matthewfeickert]

I'm stuck on Binder configuration, so I've asked in https://github.com/orgs/jupyter-book/discussions/2496.

[matthewfeickert]

From https://github.com/orgs/jupyter-book/discussions/2511#discussioncomment-15095723 we'll lose Google Collab launching for the time being with this migration.