fix license calssifier

Author: TomNicholas

setup.py

@@ -24,7 +24,7 @@
         "Development Status :: 3 - Alpha",
         "Intended Audience :: Science/Research",
         "Topic :: Scientific/Engineering",
-        "License :: OSI Approved :: Apache License",
+        "License :: OSI Approved :: Apache Software License",
         "Operating System :: OS Independent",
         "Programming Language :: Python",
         "Programming Language :: Python :: 3.9",