chg: use only a license expression.

Author: AlbertWeichselbraun

pyproject.toml

@@ -16,7 +16,6 @@ keywords = ["HTML", "converter", "text"]
 classifiers = [
         "Development Status :: 5 - Production/Stable",
         "Intended Audience :: Developers",
-        "License :: OSI Approved :: Apache Software License",
         "Topic :: Text Processing",
         "Topic :: Text Processing :: Markup :: HTML",
         "Topic :: Utilities",