Numpy2.0 migration

[smiet]

The container build is failing because the SPEC and VMEC2000 compilation step are failing.

The migration guide to numpy2.0 is given here.

I will work on getting SPEC up and running with numpy 2.0, @landreman can you have a look at VMEC? from this link it looks like this is what should be added:

[build-system]
build-backend = ...
requires = [
    # Note for packagers: this constraint is specific to wheels
    # for PyPI; it is also supported to build against 1.xx still.
    # If you do so, please ensure to include a `numpy<2.0`
    # runtime requirement for those binary packages.
    "numpy>=2.0.0rc1",
    ...
]

[project]
dependencies = [
    "numpy>=1.23.5",
]