Sync Sphinx requirement
1. Sync sphinx dependency with global requirements. It caps python 2 since
sphinx 2.0 no longer supports Python 2.7.
2. Remove unncessary "=="
Change-Id: Id733fe1f513e756eb7bb2e8314bdb5dacc5dacd3
diff --git a/HACKING.rst b/HACKING.rst
index cd3c49c..3392185 100644
--- a/HACKING.rst
+++ b/HACKING.rst
@@ -1,4 +1,4 @@
openstack Style Commandments
-===============================================
+============================
Read the OpenStack Style Commandments https://docs.openstack.org/hacking/latest/