Configure aodh coordination backend_url

Add ability to configure aodh coordination backend_url from
coordination_backend:redis pillar if defined

Related-Prod: PROD-29126

Change-Id: I5f9b98c472be31e6344b438515d4075a959c2c1d
(cherry picked from commit f4ba9fa4fe1069bf639c1d8e523b9ef828cc5f6e)

Change-Id: I5f9b98c472be31e6344b438515d4075a959c2c1d
7 files changed