improve testing of the helm chart

[edevosc2c]

add more testing in order to be sure that all the parameters in the values work great when changing things for example.

reddit discussion: https://old.reddit.com/r/kubernetes/comments/1be15b8/helm_templating_language_was_a_mistake_90_of_helm/

interesting tools:

• https://docs.kubelinter.io
• https://github.com/helm-unittest/helm-unittest
• https://github.com/yannh/kubeconform