The docker-compose.yml you get still on docker-compose version 2 which is not supported for swarm as far as i know. To use swarm, docker-compose.yml needs to be configured on version 3.x.
this docker-compose.yml has mem_limit configuration for several services, which is also not supported in docker compose version 3.x and needs to be replaced with deploy.resources config. All these gaps indicates that the docker-compose.yml supplied by alfresco is not swarm ready. But can be worked to make it compatible for swarm.
Docker has provided a "--compatibility" mode option for docker-compose in order to use v3.x docker-compose.yml without swarm while working on dev activities, it is not recommended for production. You will get a warning when try to use v3.x docker-compose.yml to launch containers without swarm.
To silent the warning, following command can be used, if testing without swarm:
docker-compose -f ./docker-compose.yml --compatibility up
or -- if there are custom build configurations defined in docker-compose.
docker-compose -f ./docker-compose.yml --compatibility up --build
Once you changed the docker-compose.yml to v3, it will be ready for swarm.
(ACSCE, AWS SAA, Azure Admin)