Currently the mwgate-npm-node-6-docker jobs all seem to fail with.
Warning: Cannot find module 'ajv/lib/compile/equal' Use --force to continue.
e.g. see
https://integration.wikimedia.org/ci/job/mwgate-npm-node-6-docker/61313/console
https://integration.wikimedia.org/ci/job/mwgate-npm-node-6-docker/61312/console