remove deprecated license classifier

Author: raymar9

pyproject.toml

@@ -8,7 +8,6 @@ license = "GPL-2.0-only"
 readme = "README.md"
 classifiers = [
     "Development Status :: 5 - Production/Stable",
-    "License :: OSI Approved :: GNU General Public License v2 (GPLv2)",
     "Programming Language :: Python :: 3",
     "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",