[CORD-2889]
Change to using premade `postgres` container

Change-Id: I3f4dc65d7b6957cbd9b8b7d5d3dc23045d4b1a82
diff --git a/scenarios/single/config.yml b/scenarios/single/config.yml
index 007aba8..adb25cf 100644
--- a/scenarios/single/config.yml
+++ b/scenarios/single/config.yml
@@ -77,10 +77,11 @@
   - "xosproject/chameleon"
   - "xosproject/xos-synchronizer-base"
   - "nginx"
+  - "node"
   - "onosproject/onos"
   - "opencord/mavenrepo"
+  - "postgres"
   - "redis"
-  - "node"
   - "sebp/elk"
 
 # Ansible Inventory