为WxErrorException添加一个构造方法，用于必要时打印出错误根源信息

weixin-java-common/src/main/java/me/chanjar/weixin/common/exception/WxErrorException.java

@@ -13,6 +13,11 @@ public class WxErrorException extends Exception {
     this.error = error;
   }
 
+  public WxErrorException(WxError error, Throwable cause) {
+    super(error.toString(), cause);
+    this.error = error;
+  }
+
   public WxError getError() {
     return this.error;
   }