socialweb-computer GitLab fixture project

scripts/gitlab-fixture.sh up creates this template as a project named fixture-probe on a fresh GitLab CE fixture, and commits deploy/gitlab-fixture/template/ to its main branch.

The project runs one job, clone-probe. The job runs on a runner tagged socialweb-computer-fixture and proves that the runner cloned the project: it checks that .gitlab-ci.yml and README.md are present and prints the commit SHA as FIXTURE_CLONE_OK.