fix: update pad token in tokenizer following upstream

tokenizer_config.json

@@ -9071,14 +9071,6 @@
       "rstrip": false,
       "single_word": false,
       "special": true
-    },
-    "201134": {
-      "content": "<|finetune_right_pad_id|>",
-      "lstrip": false,
-      "normalized": false,
-      "rstrip": false,
-      "single_word": false,
-      "special": true
     }
   },
   "bos_token": "<|begin_of_text|>",
@@ -9090,7 +9082,7 @@
     "attention_mask"
   ],
   "model_max_length": 262144,
-  "pad_token": "<|finetune_right_pad_id|>",
+  "pad_token": "<|finetune_right_pad|>",
   "processor_class": "Llama4Processor",
   "tokenizer_class": "PreTrainedTokenizer"
 }