feat: update podAnnotations rendering for better flexibility.

[matthisholleville]

This modification enhances the flexibility of podAnnotations. It provides the option to utilize evaluation functions for an locale configmap, for example.

In my scenario, I'm using this chart as a dependency, and I have a local configmap. Therefore, I want the pods to rollout when the locale configmap is modified.

...

  podAnnotations:
    checksum/local-environment: {{ include (print $.Template.BasePath "/my-local-configmap.yaml") . | sha256sum }}

...

This modification doesn't alter the current functionality.

[dkorunic]

Merged, thanks @matthisholleville!