fix(license): update pypi license info

Author: chenrui333

pyproject.toml

@@ -17,7 +17,7 @@ classifiers = [
     "Development Status :: 1 - Planning",
     "Environment :: Console",
     "Intended Audience :: Developers",
-    "License :: OSI Approved :: MIT License",
+    "License :: OSI Approved :: BSD-3-Clause",
     "Natural Language :: English",
     "Operating System :: OS Independent",
     "Programming Language :: Python :: 3",