update:去掉大写

@@ -54,7 +54,7 @@ class Signature
      */
      */
     public static function encode(string $string): string
     public static function encode(string $string): string
     {
     {
-        return strtoupper(md5($string));
+        return md5($string);
     }
     }
 
 
     /**
     /**