Add helm dry-run to makefile & to the 'test' make command

[kfswain]

Issues like: #1630 are preventable through simple helm dry-run validation. WE should add this to our CI command. It should be reasonably lightweight and prevents simple helm config issues.

[liu-cong]

We just need to run helm template instead of helm install, and validate the command generates a yaml. We could further dry run the yaml on a k8s cluster.

Note there are numerous ways of configure values.yaml, we should at least cover a few important cases that are documented in the README