Mark Python 3.9 as supported
... because it is part of tested runtimes since Yoga[1].
[1]
@@ -19,6 +19,8 @@ classifier =
Programming Language :: Python :: 3.6
Programming Language :: Python :: 3.7
Programming Language :: Python :: 3.8
+ Programming Language :: Python :: 3.9
+
[global]
setup_hooks =
pbr.hooks.setup_hook
