Fix generics in EppXmlTransformer.unmarshal to not be only on the return type.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=124914271

javatests/google/registry/tools/GenerateEscrowDepositCommandTest.java

@@ -216,7 +216,7 @@ public class GenerateEscrowDepositCommandTest
   }
 
   public static Object unmarshal(byte[] xml) throws XmlException {
-    return XjcXmlTransformer.unmarshal(new ByteArrayInputStream(xml));
+    return XjcXmlTransformer.unmarshal(Object.class, new ByteArrayInputStream(xml));
   }
 
   private static ImmutableMap<String, Long> mapifyCounts(XjcRdeHeader header) {