Update tokenizer_config.json

Hard-code needed tokenization config

tokenizer_config.json

@@ -10,5 +10,10 @@
   "strip_accents": null,
   "tokenize_chinese_chars": true,
   "tokenizer_class": "BertTokenizer",
-  "unk_token": "[UNK]"
+  "unk_token": "[UNK]",
+  "return_tensors": "pt",
+  "max_length": 256,
+  "add_special_tokens": false,
+  "return_attention_mask": true,
+  "return_token_type_ids": false
 }