Adjust .gitreview

The labs branch is based on the old zuul-config@labs repo. Update
project name in .gitreview

Change-Id: I96ba8b82aec3859aa4bf6295b98443fecfa4ed68
Move layout file to /zuul/

Change-Id: Ied91b3d1067d11b8660957de13e04f220c379053