Add metrics to PublishDnsUpdatesAction

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131190862

java/google/registry/module/backend/BackendComponent.java

@@ -47,6 +47,7 @@ import javax.inject.Singleton;
 @Component(
     modules = {
         AppIdentityCredentialModule.class,
+        BackendMetricsModule.class,
         BigqueryModule.class,
         ConfigModule.class,
         DatastoreServiceModule.class,