Sasmodel not supporting numpy 2.x, re-check when available

[bobleesj]

Running

        print(load_model_info("ellipsoid"))

provides the following error:

===================================================== ERRORS ======================================================
_______________________________________ ERROR collecting tests/test_sas.py ________________________________________
tests/test_sas.py:66: in <module>
    from sasmodels.core import load_model, load_model_info
/Users/imac/miniconda3/envs/srfit_env/lib/python3.11/site-packages/sasmodels/core.py:22: in <module>
    from . import generate
/Users/imac/miniconda3/envs/srfit_env/lib/python3.11/site-packages/sasmodels/generate.py:173: in <module>
    from .modelinfo import Parameter
/Users/imac/miniconda3/envs/srfit_env/lib/python3.11/site-packages/sasmodels/modelinfo.py:82: in <module>
    def parse_parameter(name, units='', default=np.NaN,
/Users/imac/miniconda3/envs/srfit_env/lib/python3.11/site-packages/numpy/__init__.py:400: in __getattr__
    raise AttributeError(
E   AttributeError: `np.NaN` was removed in the NumPy 2.0 release. Use `np.nan` instead.

How to navigate for now

Reinstall numpy:

    Found existing installation: numpy 2.1.3
    Uninstalling numpy-2.1.3:
      Successfully uninstalled numpy-2.1.3
Successfully installed numpy-1.26.4

======== 2 passed, 2 warnings in 3.74s =========

Reference

There is a pending PR below.

SasView/sasmodels#613