maven test run fails on OpenSuse

What steps does it take to reproduce the issue?
Run "mvn package" or "mvn test" on (OpenSuse Tumbleweed/Leap 15) linux systems.

• When does this issue occur?
  On systems where file "/etc/hosts" does not contain other entries than localhost.

• What happens?
  Tests fail. In SystemConfig.java "null" is returned from

try {
            return "https://" + InetAddress.getLocalHost().getCanonicalHostName();
        } catch (UnknownHostException e) {
            return null;
        }

because InetAddress.getLocalHost() from java.net throws UnknowHostException. (getCanonicalHostName searches for name in /etc/hosts). This lets e.g.

job.add("includedInDataCatalog", Json.createObjectBuilder()
                .add("@type", "DataCatalog")
                .add("name", installationBrandName)
                .add("url", SystemConfig.getDataverseSiteUrlStatic())

in DatasetVersion.java fail.

• To whom does it occur (all users, curators, superusers)?
  Users on OpenSuse systems trying to compile dataverse

• What did you expect to happen?
  Test should pass

Which version of Dataverse are you using?
v5.14

Start by reading SystemConfig.java, especially the hostname lookup that returns null, and DatasetVersion.java where getDataverseSiteUrlStatic() is used. Run mvn test or mvn package on an OpenSuse system whose /etc/hosts contains only localhost. Done means the affected tests pass without requiring additional host entries.