Need a job for the osbuilder repo

[jodh-intel]

https://github.com/clearcontainers/osbuilder doesn't appear to have an associated Jenkins job.

[grahamwhaley]

as in, we don't currently use Jenkins as a CI platform for osbuilder? Sure - maybe we should discuss here what we would expect the CI to do with osbuilder PRs? It is not like the other parts of the runtime (runtime, proxy, agent, shim) - so, it's not clear to me what we'd check.