Remove condition field from depends_on for Docker Compose version 3 file.

[porterdarby]

Docker Compose version 3 does not support the condition field for depends_on objects (see https://docs.docker.com/compose/compose-file/compose-file-v3/#depends_on). The current use of condition can be confusing (I was confused by it at first).

This change removes the condition fields and makes the depends_on a list.

This should present no problems with the current state of the application as it simply fixes a yaml file structure.

[boring-cyborg]

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[mik-laj]

Docker Compose supports condition field. This prevents the container from running until the service reports that it is healthy.
https://github.com/docker/compose/blob/c81046aac0ce1360f1bab64368f9a318c593d82a/compose/config/compose_spec.json#L184-L195
https://github.com/docker/compose/blob/0bea52b18dda3de8c28fcfb0c80cc08b8950645e/compose/service.py#L756-L757
It is also supported by compose spec:
https://github.com/compose-spec/compose-spec/blob/b7fb5b65fff19651ecdb2d4d3232b01fb6866f70/schema/compose-spec.json#L184-L196
To me, it looks like an issue in the docker documentation.

See also: #13446

[porterdarby]

Thanks for correcting me here. I'll see if there are some tests or something over on the Docker side and attempt to clarify that documentation. I made a quick little test locally, and the "depender" service timed out while waiting for the "dependee" service to become healthy.