Modify tutorials for rendering on gadopt.org#3

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angus-g wants to merge 5 commits intomainfrom

angus-g/website-deploy

Commits on Feb 11, 2024

Work only on 01-spd-helmholtz.ipynb to start with
angus-g
committed

Commits on Feb 12, 2024

Explicitly import triplot from firedrake
angus-g
committed

Commits on Feb 22, 2024

Ensure that tutorials 6 and 7 are valid after recent changes.
drhodrid
committed

Commits on Apr 17, 2024

Disable non-rendered tutorials for now
angus-g
committed

Commits on Apr 18, 2024

Hide exercise cells from rendering
angus-g
committed