Action to automatically re-lock projects

[maximlt]

Placeholder for now, I just wanted to link to this project that maybe useful for this endeavor: https://github.com/chrisjsewell/pytest-notebook

EDIT: The idea is that we can't just run this hypothetical action that updates a lock file and merges the updated project without running tests. The current tests are just smoke tests; they'll pass if a notebook runs entirely without raising an error. So it's possible a dependency update leads to changes in notebook outputs that are significant and yet don't raise an error. So we need a way, automated or not, to validate the new dependencies haven't introduced unrequired changes.