Wire in MetricReporter into the backend servlet to publish metrics

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=130468842

java/google/registry/monitoring/metrics/MetricRegistryImpl.java

@@ -81,7 +81,6 @@ public final class MetricRegistryImpl implements MetricRegistry {
       String description,
       String valueDisplayName,
       ImmutableSet<LabelDescriptor> labels) {
-
     Counter metric = new Counter(name, description, valueDisplayName, labels);
     registerMetric(name, metric);
     logger.info("Registered new counter: " + name);