Run samples from alfalfa-notebooks with CI

[anyaelena]

All published notebooks in alfalfa-notebooks should be tested.

Run in this repo or in Alfalfa-notebooks??
Close down alfalfa-notebooks and migrate to tests here?

[TShapinsky]

I've created an example github action which allows other repositories to easily include alfalfa in their CI. In addition I have a proof of concept for triggering actions in other repositories. It would be fairly easy to set up a system where, when there is an update to develop or a release, alfalfa-notebooks are automatically tested.