from-scratch should not be run twice

The idea was to create an env and stick with it if it works. But if you keep running it over and over again in the same CI machine, it might break the wheels because of dependency changes.

We need a script to update the environment whenever we need to do it. I agree that updating the environment may break API/ABI against pre-compiled wheels. The admin in question should then re-run the nightlies in that case.

Status changed to closed