fix typo in postgres image name

Change-Id: I270899888d866ecc7e29da69d0d2ddaf88f95a97
diff --git a/defaults/docker_images.yml b/defaults/docker_images.yml
index 60d2bb9..a7b5a8e 100644
--- a/defaults/docker_images.yml
+++ b/defaults/docker_images.yml
@@ -65,7 +65,7 @@
         name: openldap:1.1.8
       - registry: ${_param:mcp_docker_registry}/mirantis/external/library
         target_registry: ${_param:local_docker_client_registry_target_registry}/mirantis/external/library
-        name: postgresql:9.6.10
+        name: postgres:9.6.10
       - registry: ${_param:mcp_docker_registry}/mirantis/cicd
         target_registry: ${_param:local_docker_client_registry_target_registry}/mirantis/cicd
         name: phpldapadmin:${_param:apt_mk_version}