Update setup.cfg

Updating classifiers

Author: nbashir97

setup.cfg

@@ -10,8 +10,9 @@ license = MIT
 license_files = file: LICENSE
 url = https://github.com/nbashir97/effectsize
 classifiers =
-    License :: OSI Approved :: MIT License
     Programming Language :: Python :: 3
+    Operating System :: OS Independent
+    License :: OSI Approved :: MIT License
 platform = any
 
 [options]