notebook ci [reminder: update bpz install]

[OliviaLynn]

Edit: Implemented, but keeping this up as a reminder to remove the line in our notebooks workflows that install bpz from a branch (to get the updated directory version)

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I am working on:

• An improved way to check (all) our notebooks are working

Considerations:

• Run all the notebooks, not just the ones that had been "featured" in our documentation when I had originally taken on the notebooks TLC mission
• Put this in a separate workflow that does not create PRs or quibble with output HTMLs
• Maybe, however, temporarily stashing HTML outputs to still let the person who triggered the workflow to quickly scan things over