Address review comments and add docs

tests/prompt_strategies/test_chat_template_utils.py

@@ -7,7 +7,7 @@ import pytest
 from transformers import AutoTokenizer
 
 from axolotl.utils.chat_templates import (
-    _TEMPLATES,
+    _CHAT_TEMPLATES,
     extract_chat_template_args,
     get_chat_template,
 )
@@ -27,7 +27,7 @@ class TestGetChatTemplateUtils:
 
     def test_known_chat_template(self):
         chat_template_str = get_chat_template("llama3")
-        assert chat_template_str == _TEMPLATES["llama3"]
+        assert chat_template_str == _CHAT_TEMPLATES["llama3"]
 
     def test_invalid_chat_template(self):
         with pytest.raises(ValueError) as exc: