优化XStreamTransformer

weixin-java-open/src/main/java/me/chanjar/weixin/open/util/xml/XStreamTransformer.java

@@ -60,7 +60,6 @@ public class XStreamTransformer {
    */
   private static void registerClass(Class<?> clz) {
     XStream xstream = XStreamInitializer.getInstance();
-    xstream.setClassLoader(Thread.currentThread().getContextClassLoader());
 
     xstream.processAnnotations(clz);
     xstream.processAnnotations(getInnerClasses(clz));