Delete MultiplyingCloudDnsWriter

Now that the large zone re-signing test is complete, we no longer need it.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=199507075

java/google/registry/dns/writer/clouddns/CloudDnsWriterModule.java

@@ -59,7 +59,6 @@ public abstract class CloudDnsWriterModule {
   @IntoMap
   @StringKey(CloudDnsWriter.NAME)
   abstract DnsWriter provideWriter(CloudDnsWriter writer);
-
   @Provides
   @IntoSet
   @Named("dnsWriterNames")