Option to set a custom config

[Slava]

During the the Manual run inside Kubernetes via Job #7 it was required to pass a custom config to the app, because as for now it is a single way to configure the application.

We already have some requests to add configuration options, but until that is may be useful to have an option to set a custom app config.

Currently we handle that by the custom entrypoint and container environment variables

        env:
        - name: CONFIG
          value: "/opt/Configuration.cs"

[Slava]

Looks like we are fine with running just with CLI switches and ENV variables and custom config is not required, at least at this point.

I case of need, we can return to this issue again.