Gating sanity-test job for patches to voltha-helm-charts repo

Create a gating test job for patchsets to the voltha-helm-charts repo.  This job should look like the other sanity-tests jobs – it should use kind-voltha to run a BBSim test using the modified charts.

A possible issue is that right now the test might not work with the images loaded by the published charts.  We may need to release some components and update the charts first.

For the time being, we can test the charts using :voltha-2.1 images.