@Override
    public Set<FileReference> listFileReferences(ApplicationId applicationId) {
        return applicationMapper.listApplications(applicationId).stream()
                .flatMap(app -> app.getModel().fileReferences().stream())
                .collect(toSet());
    }
Given baseIdSegment search/ and id search/container/default.0, return search/container
@return id segment with one extra level from the id appended
configserver/src/main/java/com/yahoo/vespa/config/server/application/TenantApplications.java