always add short container id as net alias

This matches what docker does. Also make sure the net aliases are also
shown when the container is stopped.

docker-compose uses this special alias entry to check if it is already
correctly connected to the network. [1]
Because we do not support static ips on network connect at the moment
calling disconnect && connect will loose the static ip.

Fixes #11748

[1] 0bea52b18d/compose/service.py (L663-L667)

Signed-off-by: Paul Holzinger <pholzing@redhat.com>

test/compose/test-compose

@@ -247,6 +247,7 @@ function podman() {
 	--storage-driver=vfs \
         --root    $WORKDIR/root    \
         --runroot $WORKDIR/runroot \
+        --cni-config-dir $WORKDIR/cni \
         "$@")
     echo -n "$output" >>$WORKDIR/output.log
 }