changed key "description-file" to "description_file" to fix issues bu…

[SebastianVivoverse]

changed key "description-file" to "description_file" to fix issues building with setuptools v78 or higher.

Old error:

#8 8.790         File "/tmp/pip-build-env-behom6lj/overlay/lib/python3.11/site-packages/setuptools/dist.py", line 629, in _enforce_underscore
#8 8.790           raise InvalidConfigError(
#8 8.790       setuptools.errors.InvalidConfigError: Invalid dash-separated key 'description-file' in 'metadata' (setup.cfg), please use the underscore name 'description_file' instead.
#8 8.790       [end of output]

See breaking change in setuptools
https://setuptools.pypa.io/en/stable/history.html#v78-0-0