use github.com with zuul-cloner
use github.com with zuul-cloner

had worked prior to https://review.elasticdb.org/#/c/3151/
I was overambitious trying to move off github.com here.
needs it for openstack repos.

Change-Id: I627cabddb79931a6c7e3b26e28acf769727742a4

Tesora/tesora-project-config,Tesora/tesora-project-config