Fix eos_token in tokenizer_config.json to use im_end for Instruct Model

eos_token for instruct model should be im_end instead of the original eos token in base model

tokenizer_config.json

@@ -82,7 +82,7 @@
   ],
   "bos_token": "[BOS]",
   "clean_up_tokenization_spaces": false,
-  "eos_token": "[EOS]",
+  "eos_token": "<|im_end|>",
   "extra_special_tokens": {},
   "model_max_length": 1048576,
   "pad_token": "[PAD]",