@Override
  protected Observation convertToObservation(final DataPointSnapshot sample) {
    final List<String> labelValues = getLabelValues(sample.getLabels());

    return new Observation(
        category, name, ((GaugeSnapshot.GaugeDataPointSnapshot) sample).getValue(), labelValues);
  }
A Prometheus supplied gauge collector. A supplied gauge collector is one which actual value is
kept outside the metric system, for example in an external library or to calculate the value only
on demand when a metric scrape occurs.
metrics/core/src/main/java/org/hyperledger/besu/metrics/prometheus/PrometheusSuppliedGauge.java