Update tokenizer config with inspiration from eric's dolphin.

tokenizer_config.json

@@ -29,7 +29,7 @@
   },
   "additional_special_tokens": [],
   "bos_token": "<s>",
-  "chat_template": "{{ bos_token }}{% for message in messages %}{% if message['role'] == 'system' %}\nSYSTEM: {{ message['content']|safe }}\n{% elif message['role'] == 'user' %}\nUSER: {{ message['content']|safe }}\n{% elif message['role'] == 'assistant' %}\nASSISTANT: {{ message['content']|safe }}\n{% else %}{{ raise_exception('Only user, assistant, and system roles are supported!') }}{% endif %}\n{% endfor %}{{ eos_token }}",
+  "chat_template": "{% if not add_generation_prompt is defined %}{% set add_generation_prompt = false %}{% endif %}{% for message in messages %}{% if message['role'] == 'system' %}{{ 'SYSTEM: ' + message['content'] + '\n' }}{% elif message['role'] == 'user' %}{{ 'USER: ' + message['content'] + '\n' }}{% elif message['role'] == 'assistant' %}{{ 'ASSISTANT: ' + message['content'] + '\n' }}{% else %}{{ raise_exception('Unsupported role: ' + message['role']) }}{% endif %}{% endfor %}{% if add_generation_prompt %}ASSISTANT: {% endif %}",
   "clean_up_tokenization_spaces": false,
   "eos_token": "</s>",
   "legacy": true,