Remove unnecessary generic type arguments

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

java/google/registry/flows/domain/DomainPricingLogic.java

@@ -210,6 +210,6 @@ public final class DomainPricingLogic {
         return Optional.of(token);
       }
     }
-    return Optional.<LrpTokenEntity>empty();
+    return Optional.empty();
   }
 }