Remove unnecessary generic type arguments

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=175155365

java/google/registry/monitoring/whitebox/EppMetric.java

@@ -178,7 +178,7 @@ public abstract class EppMetric implements BigQueryMetric {
     public Builder setTlds(ImmutableSet<String> tlds) {
       switch (tlds.size()) {
         case 0:
-          setTld(Optional.<String>empty());
+          setTld(Optional.empty());
           break;
         case 1:
           String tld = Iterables.getOnlyElement(tlds);

java/google/registry/monitoring/whitebox/MetricsExportAction.java

@@ -67,7 +67,7 @@ public class MetricsExportAction implements Runnable {
       // Filter out the special parameters that the Action is called with.  Everything that's left
       // is returned in a Map that is suitable to pass to Bigquery as row data.
       Map<String, Object> jsonRows =
-          ImmutableMap.<String, Object>copyOf(
+          ImmutableMap.copyOf(
               filterKeys(parameters, not(in(SPECIAL_PARAMS))).entries());
       TableDataInsertAllResponse response = bigquery.tabledata()
           .insertAll(