Use long syntax for bind volumes

[dmarteau]

• Prevent creation on the fly of inexistent path on host with root owner.
• See https://docs.docker.com/compose/compose-file/compose-file-v3/#long-syntax-3

[dmarteau]

@dmarteau what the difference between bind and volume?

• 'bind`: bindmount a host path in the container
• 'volume': use a named volume (created with docker compose global volumes section or docker volume create ...)

cf https://docs.docker.com/storage/bind-mounts/