Update tokenizer_config.json

added src_lang and tgt_lang language arg as default

tokenizer_config.json

@@ -110,8 +110,8 @@
   "pad_token": "<pad>",
   "sep_token": "</s>",
   "sp_model_kwargs": {},
-  "src_lang": null,
-  "tgt_lang": null,
+  "src_lang": "en",
+  "tgt_lang": "ta",
   "tokenizer_class": "M2M100Tokenizer",
   "tokenizer_file": null,
   "unk_token": "<unk>"