Update pyproject.toml

[enzbus]

This might be enough to fix the failure.
It was on a piece of the github yaml that we weren't testing.

[enzbus]

The build_mkl errors on mac are probably related to the setuptools version, I can't reproduce it locally. If they are blocking the release you could de-activate them.

[bodono]

The failure is coming from here, which is skipped unless the wheels are being deployed. Is there some way to run meson for python 3.7? If not we can just disable that version.

[enzbus]

We can probably drop 3.7, let me review.