I managed to install delete-project plugin after following this thread:
https://groups.google.com/forum/#!topic/repo-discuss/hbBc2TUhl7s
and then install according to:
https://gerrit-review.googlesource.com/Documentation/cmd-plugin-install.html
P.S. I build the jar following the below steps:
- git clone --recursive https://gerrit.googlesource.com/gerrit
- cd gerrit
- git clone --recursive https://gerrit.googlesource.com/plugins/delete-project
- buck build delete-project:delete-project
You should then find the delete-project.jar in buck-out/gen/delete-project/delete-project.jar