Update tokenization_qwen.py

Fix as per https://github.com/QwenLM/Qwen-VL/issues/287

tokenization_qwen.py

@@ -111,7 +111,6 @@ class QWenTokenizer(PreTrainedTokenizer):
         quad_end_tag='</quad>',
         **kwargs,
     ):
-        super().__init__(**kwargs)
         self.image_start_tag = image_start_tag
         self.image_end_tag = image_end_tag
         self.image_pad_tag = image_pad_tag
@@ -128,6 +127,7 @@ class QWenTokenizer(PreTrainedTokenizer):
             image_start_tag, image_end_tag,
             image_pad_tag
         )
+        super().__init__(**kwargs)
 
         self.errors = errors  # how to handle errors in decoding