fix: SetuptoolsDeprecationWarning: Invalid dash-separated options

/home/anders/.cache/uv/builds-v0/.tmpXAxITl/lib/python3.12/site-packages/setuptools/dist.py:589: SetuptoolsDeprecationWarning: Invalid dash-separated options
!!

        ********************************************************************************
        Usage of dash-separated 'description-file' will not be supported in future
        versions. Please use the underscore name 'description_file' instead.

        This deprecation is overdue, please update your project and remove deprecated
        calls to avoid build errors in the future.

        See https://setuptools.pypa.io/en/latest/userguide/declarative_config.html for details.
        ********************************************************************************

!!
  opt = self.warn_dash_deprecation(opt, section)

Signed-off-by: Anders Kaseorg <[email protected]>

Author: andersk

setup.cfg

@@ -2,7 +2,7 @@
 universal = 1
 
 [metadata]
-description-file = README.md
+description_file = README.md
 license = MIT
 
 [flake8]