Remove helm2 support from helm chart

[OlleLarsson]

• Which image of the operator are you using?
  • registry.opensource.zalan.do/acid/postgres-operator:v1.7.1
• Where do you run it - cloud or metal? Kubernetes or OpenShift?
  • k8s
• Are you running Postgres Operator in production?
  • No
• Type of issue?
  • Feature request :) ?

Helm2 has been deprecated for a long time now and I was surprised to see that it seems like the helm chart still supports helm2 as I got the following messages when installing the operator

manifest_sorter.go:192: info: skipping unknown hook: "crd-install"
manifest_sorter.go:192: info: skipping unknown hook: "crd-install"
manifest_sorter.go:192: info: skipping unknown hook: "crd-install"

I would say that it is time to remove helm2 support.

• Remove crds.yaml template
• Remove helm values
• Remove deprecated helm hook annotation from crds

[FxKu]

Was it already that long ago? Felt like yesterday when these hooks had to be introduced 😄
Makes sense to me to remove them. Hope nobody starts crying then.

[OlleLarsson]

Okay maybe I exaggerated a little bit 😄
https://helm.sh/blog/helm-v2-deprecation-timeline/