[Core] Change openstack-dev to openstack-discuss.

The openstack-dev address is replaces by openstack-discuss.

Change-Id: Ia60662c3b1cc6cce7b735e10cbf7b5f48017b1e6

setup.cfg

@@ -4,7 +4,7 @@ summary = Heat templates for deploying OpenStack with OpenStack.
 description-file =
     README.rst
 author = OpenStack
-author_email = openstack-dev@lists.openstack.org
+author_email = openstack-discuss@lists.openstack.org
 license = Apache License (2.0)
 home-page = https://git.openstack.org/cgit/openstack/tripleo-heat-templates
 classifier =