Added the missing directory to run a docker container without volume

[jtabet]

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Description

This change allows to run a docker container without mounting any volume.

Type of PR

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• Bugfix
• Feature implementation
• Refactor of code (without functional changes)
• Documentation improvements
• Test improvements

Testing

docker build -t mimic3-testing:latest .
docker run --rm -p 59125:59125 mimic3-testing

Then navigate to http://localhost:59125 and hit "speak". Should work without error.

Documentation

Does documentation for this already exist? Are there docstrings on all the public methods you added or modified? Have these been updated?

CLA

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[jtabet]

Available here: https://hub.docker.com/r/jtabet/mimic3