public final Metrics getMetrics() {
        CollectMetrics collector = new CollectMetrics();
        consumeMetrics(collector);
        return collector.metrics;
    }
Get the Metrics registered for this service. Metrics are fetched over HTTP
if a metric http port has been defined, otherwise from log file
metrics-proxy/src/main/java/ai/vespa/metricsproxy/service/VespaService.java