Remove unnecessary generic type arguments

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

java/google/registry/export/PublishDetailReportAction.java

@@ -109,7 +109,7 @@ public final class PublishDetailReportAction implements Runnable, JsonAction {
             driveFolderId,
             gcsBucketName,
             gcsObjectName);
-        return ImmutableMap.<String, Object>of("driveId", driveId);
+        return ImmutableMap.of("driveId", driveId);
       } catch (FileNotFoundException e) {
         throw new IllegalArgumentException(e.getMessage(), e);
       }

java/google/registry/export/SyncGroupMembersAction.java

@@ -134,7 +134,7 @@ public final class SyncGroupMembersAction implements Runnable {
     for (final Registrar registrar : dirtyRegistrars) {
       try {
         retrier.callWithRetry(() -> syncRegistrarContacts(registrar), RuntimeException.class);
-        resultsBuilder.put(registrar, Optional.<Throwable>empty());
+        resultsBuilder.put(registrar, Optional.empty());
       } catch (Throwable e) {
         logger.severe(e, e.getMessage());
         resultsBuilder.put(registrar, Optional.of(e));