Fix Ubuntu18.04 nodes

Some of these jobs were calling a non existent node

Change-Id: I99c724a440d0db5b2444e9b120e05e39685d6796
Issue-ID: CIMAN-33
Signed-off-by: Jessica Wagantall <jwagantall@linuxfoundation.org>
diff --git a/jjb/appc/appc-master.yaml b/jjb/appc/appc-master.yaml
index 404fe9e..7bd08ae 100644
--- a/jjb/appc/appc-master.yaml
+++ b/jjb/appc/appc-master.yaml
@@ -42,7 +42,7 @@
     sonarcloud-project-key: '{sonarcloud_project_organization}_{project-name}'
     sonar-mvn-goal: '{sonar_mvn_goal}'
     cron: '@daily'
-    build-node: ubuntu1804-builder-8c-8g
+    build-node: ubuntu1804-builder-4c-4g
     project: 'appc'
     project-name: 'appc'
     branch: 'master'