Fixes#16613
The issue was caused by two test files having the same module name
(test_transformation.py) in different directories, which caused pytest
to fail with an import file mismatch error.
Changes:
- Renamed tests/test_litellm/llms/xai/responses/test_transformation.py
to test_xai_responses_transformation.py
- Renamed tests/test_litellm/llms/openai_like/chat/test_transformation.py
to test_openai_like_chat_transformation.py
Both files now have unique, descriptive names that reflect their
specific test purposes and prevent module name collisions.
