Fix for payment express to cope with change in where I think html_entities belongs

Author: eileenmcnaughton

vendor/omnipay/paymentexpress/src/Message/PxPayAuthorizeRequest.php

@@ -245,4 +245,14 @@ protected function createResponse($data)
     {
         return $this->response = new PxPayAuthorizeResponse($this, $data);
     }
+
+    /**
+     * Get the request return URL.
+     *
+     * @return string
+     */
+    public function getReturnUrl()
+    {
+        return htmlentities($this->getParameter('returnUrl'));
+    }
 }