Avoid random position of parameters when creating docker-compose.prod.yml

[leograba]

Every time I run the task create-production-image, the docker-compose.prod.yml is overwritten by a new file with fields in a different order.

Since I want to keep the file under Git, this makes it hard to review what are real changes and what are random property line changes. It would be nice to only modify the things that were changed in the original docker-compose.yml.