Replace scenario004 multinode with standalone

Following addition of [1], replace use of multinode with
standalone job for scenario004

1. https://review.openstack.org/#/c/619520/

Change-Id: Iff1e83dd227fc2e03924f41592f82a555053425d

zuul.d/layout.yaml

@@ -80,12 +80,12 @@
               - ^network/endpoints/.*$
               - ^common/.*$
               - zuul.d/*
-        - tripleo-ci-centos-7-scenario004-multinode-oooq-container:
+        - tripleo-ci-centos-7-scenario004-standalone:
             files:
               - ^docker/services/ceph.*$
               - ^docker/services/glance.*$
               - ^docker/services/manila.*$
-              - ci/environments/scenario004-multinode-containers.yaml
+              - ci/environments/scenario004-standalone.yaml
               - ^environments\/.*.yaml
               - ^deployed-server/.*$
               - ^network/endpoints/.*$