License Classifiers are deprecated

[NAThompson]

While building SMT using uv under python3.13, the following warning is emitted:

    building 'smt.surrogate_models.rbfclib' extension
      /home/.cache/uv/builds-v0/.tmpuPj4zT/lib/python3.13/site-packages/setuptools/dist.py:759:
      SetuptoolsDeprecationWarning: License classifiers are deprecated.
      !!
      
      ********************************************************************************
              Please consider removing the following classifiers in favor of a
      SPDX license expression:
              License :: OSI Approved :: BSD License
              See
      https://packaging.python.org/en/latest/guides/writing-pyproject-toml/#license
      for details.
      
      ********************************************************************************
      !!
        self._finalize_license_expression()

This line in the setup.py should be removed, and a license = "BSD-3-Clause" should be added to the [project] section of the pyproject.toml.

Obviously quite low priority . . .

[relf]

Thanks for the heads up!