Migrate to ubuntu1804-builder

Migrate the rest of the jobs from
ubuntu1604-builder to ubuntu1804-builder
Remove unused nodes

Change-Id: Ic43c12d3f7f8952d3248085ec103806c9b442047
Issue-ID: CIMAN-373
Signed-off-by: Jessica Wagantall <jwagantall@linuxfoundation.org>
diff --git a/jjb/so/so-libs.yaml b/jjb/so/so-libs.yaml
index 1a6bdc4..af1be77 100644
--- a/jjb/so/so-libs.yaml
+++ b/jjb/so/so-libs.yaml
@@ -36,7 +36,7 @@
     sonarcloud-project-key: '{sonarcloud_project_organization}_{project-name}'
     sonar-mvn-goal: '{sonar_mvn_goal}'
     cron: '@daily'
-    build-node: ubuntu1604-builder-4c-4g
+    build-node: ubuntu1804-builder-4c-4g
     project: 'so/libs'
     project-name: 'so-libs'
     branch: 'master'