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/rde/RdeReportActionTest.java

@@ -197,7 +197,7 @@ public class RdeReportActionTest {
 
   private static XjcRdeReportReport parseReport(byte[] data) {
     try {
-      return XjcXmlTransformer.unmarshal(new ByteArrayInputStream(data));
+      return XjcXmlTransformer.unmarshal(XjcRdeReportReport.class, new ByteArrayInputStream(data));
     } catch (XmlException e) {
       throw new RuntimeException(e);
     }