Add the delete-project Gerrit plugin

This is potentially useful for cleaning up from mistakes.

Change-Id: I801caf74e07f7f9b3e663d8267cf42bf7861c8b9

modules/openstack_project/files/jenkins_job_builder/config/projects.yaml

@@ -483,6 +483,19 @@
     jobs:
       - maven-plugin-jobs
 
+- project:
+    name: delete-project-gerrit-plugin
+    node: bare-precise
+    tarball-site: tarballs.openstack.org
+    gerrit-project: https://git.openstack.org/openstack-infra/gerrit
+    gerrit-branch: openstack/2.8.4
+    plugin-project: https://gerrit.googlesource.com/plugins/delete-project
+    plugin-name: delete-project
+    plugin-branch: master
+
+    jobs:
+      - gerrit-plugin-jobs
+
 - project:
     name: javamelody-gerrit-plugin
     node: bare-precise

modules/openstack_project/files/zuul/layout.yaml

@@ -2924,6 +2924,7 @@ projects:
       - gerrit-package
       - gerrit-package-buck
     periodic:
+      - periodic-gerrit-plugin-delete-project-gerrit-plugin
       - periodic-gerrit-plugin-javamelody-gerrit-plugin
 
   - name: openstack-infra/gerrit-powered-agenda