ci: Add vallidation of k8s objects, helm lint, etc.
ci: Add vallidation of k8s objects, helm lint, etc.

This is in prep for doing real testing of the helm chart, which should
make evaluating contributions much better.

Also, it will allow us to shortcircuit and gate deploys to prevent
disasters on merge.

Bug: T256689

yuvipanda/paws,yuvipanda/paws