Add chat_template for eval compatibility

tokenizer_config.json

@@ -219,5 +219,6 @@
   "model_max_length": 1000000000000000019884624838656,
   "pad_token": null,
   "tokenizer_class": "GPTNeoXTokenizer",
-  "unk_token": "<|endoftext|>"
-}
+  "unk_token": "<|endoftext|>",
+  "chat_template": "{{ bos_token }}{% for message in messages %}{% if message[\"role\"] == \"system\" %}{{ \"<|system|>\n\" + message[\"content\"] + \"\n\" }}{% elif message[\"role\"] == \"user\" %}{{ \"<|user|>\n\" + message[\"content\"] + \"\n\" }}{% elif message[\"role\"] == \"assistant\" %}{% if not loop.last %}{{ \"<|assistant|>\n\"  + message[\"content\"] + eos_token + \"\n\" }}{% else %}{{ \"<|assistant|>\n\"  + message[\"content\"] + eos_token }}{% endif %}{% endif %}{% if loop.last and add_generation_prompt %}{{ \"<|assistant|>\n\" }}{% endif %}{% endfor %}"
+}