CI job "test" fails due to missing ci lint API endpoint

My recent CI job (https://gitlab.torproject.org/tpo/tpa/ci-templates/-/jobs/456261) failed because the gitlab.torproject.org/api/v4/ci/lint endpoint is returning a 404. It looks like the lint API may have changed according to the docs: https://docs.gitlab.com/ee/api/lint.html#validate-a-projects-ci-configuration. We may need to change the CI linting script to accomodate that.