Check if project exists for CI API
This is a follow up for https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/7831#note_19422903
So we just make sure that CI API cannot be accessed if the project has been soft-deleted.
This is a follow up for https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/7831#note_19422903
So we just make sure that CI API cannot be accessed if the project has been soft-deleted.