There's not much value in using the fqdn for docker instance resolving
because all docker instances are usually on the same host machine. And
they can resolve each other with the short hostnames.

OTOH, relying on the fqdn has caused problems in environments where a
DNS Domain Name is provided, like for example the instances on Microsoft
Azure environment, which provide their Azure domain names. This creates
invalid OBS host name instances.

Signed-off-by: Ritesh Raj Sarraf <ritesh.sarraf@collabora.com>