Volume mounting actions in Rasa X 0.36

To add a new action server for use with Rasa X, the paradigm used to be docker volume mounting:

version: '3.4'
services:
    app:
        restart: always
        image: 'rasa/rasa-sdk:${RASA_SDK_VERSION}'
        expose:
          - '5005'
        volumes:
          - './actions:/app/actions'
        depends_on:
          - rasa-production

Is volume mounting still supported in Rasa X V 0.3+? The instructions now exclusively remark on making new action server images: Customize Your Deployment