Zuul: Remove project name

Zuul no longer requires the project-name for in-repo configuration.
Omitting it makes forking or renaming projects easier.

Change-Id: I8cdcf763538c806f3ac27826c19f2086caca6929

.zuul.yaml

 - project:
-    name: openstack/kolla-ansible
     check:
       jobs:
         - kolla-ansible-centos-source