docker-compose: Align hosts with hostname

docker-compose: Align hosts with hostname

When using Docker CE 19.x, `hostname -d` fails to properly resolve
the domainname due to changes in the way Docker sets it inside the
container.

Work around this issue by aligning the contents of `/etc/hostname`
with `/etc/hosts`, so `hostname -d` can properly determine the
domain name. This also requires calling `hostname -b` via cfg01
entrypoint.sh.

Change-Id: I697b5d9882e3d6641712a00bca10012800ee1898
Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>