Update the documentation link for doc migration

Change-Id: Ife64e74bb486c109dd565b5f24f6566d7f7bac7c
diff --git a/HACKING.rst b/HACKING.rst
index dc34b75..7faf92f 100644
--- a/HACKING.rst
+++ b/HACKING.rst
@@ -2,4 +2,4 @@
 
 ===============================================
 
-Read the OpenStack Style Commandments http://docs.openstack.org/developer/hacking/
+Read the OpenStack Style Commandments https://docs.openstack.org/hacking/latest/