ENV resource from file

[fawadasaurus]

Is your feature request related to a problem? Please describe.
Currently, the application has access to all environment variables. This is not ideal as all other resources are explicitly defined ahead of time. This is also valuable in deployment scenarios where a single secret can be stored and mounted as a filesystem directory instead of passing multiple individual secrets as environment variables to each deployed container.

Propose a solution
Environment variables should have a resource definition just like ports and file system.

resources:
  - name: env
    resource:
      kind: wick/resource/environment@v1
      vars_from:
        file:
          - .env
          - /root/.zshrc
        env:
          - ABC
          - MY_ENV_VAR

Describe alternatives you've considered
None

Additional context
None