Add support to relative paths with {path://} dynamic value

[alessiodionisi]

This feature ad a new "dynamic value" for string interpolation the name path that converts a relative path to absolute.

NOTE: This feature can replace the string regex replacer that converts any string that starts with ./ as absolute.

Usage example

Secret generator with files:

customPatches:
  secretGenerator:
    - name: my-secret
      namespace: default
      type: kubernetes.io/tls
      files:
        - tls.crt={path://./certs/tls.crt}
        - tls.key={path://./certs/tls.key}