Remove gnocchi from PROJECTS for tripleo-ci
Remove gnocchi from PROJECTS for tripleo-ci

It isn't hosted in git.openstack.org anymore, so adding it to PROJECTS
does not help.

Change-Id: Iaf0857b4b49c3aca417f4512b2b7668f32978b65

openstack-infra/project-config,openstack-infra/project-config