修改 echo 注释

WeChat/Contracts/BasicPushEvent.php

@@ -144,7 +144,7 @@ class BasicPushEvent
      * @param array $data 消息内容
      * @param boolean $return 是否返回XML内容
      * @param boolean $isEncrypt 是否加密内容
-     * @return string
+     * @return string|void
      * @throws \WeChat\Exceptions\InvalidDecryptException
      */
     public function reply(array $data = [], $return = false, $isEncrypt = false)

WeChat/Contracts/BasicWePay.php

@@ -153,14 +153,12 @@ class BasicWePay
      * 数组直接转xml数据输出
      * @param array $data
      * @param bool $isReturn
-     * @return string
+     * @return string|void
      */
     public function toXml(array $data, $isReturn = false)
     {
         $xml = Tools::arr2xml($data);
-        if ($isReturn) {
-            return $xml;
-        }
+        if ($isReturn) return $xml;
         echo $xml;
     }