routes: new /suite/default endpoint

[afrid18]

add new /suite/default endpoint for scheduling default jobs. This is a pre-task for GSoC'24 selection

Default arguments used:

{
        "--ceph": "wip-leonidc-20240331-00",
        "--ceph-repo": "https://github.com/ceph/ceph-ci.git",
        "--suite_repo": "https://github.com/ceph/ceph-ci.git",
        "--suite": "teuthology:no-ceph",
        "--machine-type": "testnode",
        "--distro": "ubuntu",
        "--distro-version": "20.04",
        "<config_yaml>": ["/teuthology/containerized_node.yaml"]
}

Success response screenshot:

Jobs ran successfully:

Checklist

• [x] Changes tested in container setup
• [x] Changes tested in non-containerized setup
• [x] Includes tests
• [ ] Documentation updated