@Override
    public AthenzAccessToken getAccessToken(List<AthenzRole> athenzRole) {
        return getAccessToken(athenzRole, List.of());
    }
Default implementation of {@link ZtsClient}

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