fix: podman-compose down should not stop the upstream dependencies.

[lisongmin]

Say there is an app service depends on a db service, when we run podman-compose down app, the db service should not be stopped.

This will fix #1260

[lisongmin]

Say there is an app service depends on db service, like:

services:
    app:
        image: myapp
        restart: always
        depends_on:
            - db
    db:
        image: mydb

The behavior of docker-compose and podman-compose is different as follows:

scenario	docker-compose behavior	current podman-compose behavior	new podman-compose behavior
down all	stop and remove db, app	same as docker-compose	same as docker-compose
down app	stop and remove app	stop and remove db, app	same as docker-compose
down db	stop and remove db	stop but failed to remove db	stop and remove db, app

podman-compose relies on podman's --requires to determine the dependency between containers.
When we try to remove the db container, podman will refuse to do so because it is required by the
app container. And we can not create a new db container without removing the old one.

Moreover, if we rename the db container, and create a new one, the dependencies will lost,
and there may be two db containers running at the same time, which is not what we want.
So we should remove both db and app containers when we want to remove the db container.

this behavior can only changed when podman support dynamic dependencies, which is not supported now.

[p12tic]

Great, thanks!