Should `package_test` be in a `tox` environment?

[nvaytet]

The package test will run on CI: https://github.com/scipp/copier_template/blob/main/template/.github/workflows/test.yml#L56

It would be useful to be able to run it easily locally with tox.

[YooSunYoung]

But if you run the tox -e test it'll run the package_test as well, no...?