@Override
    public ZToken getRoleToken(AthenzRole athenzRole, Duration expiry) {
        return getRoleToken(athenzRole.domain(), athenzRole.roleName(), expiry);
    }
Default implementation of {@link ZtsClient}

@author bjorncs
@author mortent
vespa-athenz/src/main/java/com/yahoo/vespa/athenz/client/zts/DefaultZtsClient.java