Update LegacyQueryRequest.php

在getData方法里面增加sign_type参数，这个是必需要要传入的参数，否则会报ILLEGAL_SIGN，希望尽快采纳

Author: laraveler

src/Requests/LegacyQueryRequest.php

@@ -54,7 +54,8 @@ public function getData()
             'partner'        => $this->getPartner(),
             'trade_no'       => $this->getTradeNo(),
             'out_trade_no'   => $this->getOutTradeNo(),
-            '_input_charset' => $this->getInputCharset()
+            '_input_charset' => $this->getInputCharset()，
+            ‘sign_type'      => $this->getSignType()
         ];
         $data['sign'] = $this->sign($data, $this->getSignType());