Add explicit generic type parameters to make Java 7 build happy

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=139374166

java/google/registry/flows/domain/DomainAllocateFlow.java

@@ -394,7 +394,7 @@ public class DomainAllocateFlow implements TransactionalFlow {
     FeeCreateCommandExtension feeCreate =
         eppInput.getSingleExtension(FeeCreateCommandExtension.class);
     return (feeCreate == null)
-        ? ImmutableList.of()
+        ? ImmutableList.<FeeTransformResponseExtension>of()
         : ImmutableList.of(createFeeCreateResponse(feeCreate, commandOperations));
   }