Update deprecated 'description-file' in setup.cfg

[BastienDussap]

Can't install gputils with Setuptools verision>=78

See Setuptools changelog :

"Setuptools no longer accepts options containing uppercase or dash characters in setup.cfg. Please ensure to write the options in setup.cfg using the lower_snake_case convention (e.g. Name => name, install-requires => install_requires). This is a follow-up on deprecations introduced in v54.1.0 (see #1608) and v54.1.1 (see #2592)."

[BastienDussap]

Update : Setuptolls 78.0.2.

"Postponed removals of deprecated dash-separated and uppercase fields in setup.cfg. All packages with deprecated configurations are advised to move before 2026. (#4911)"