Pandas-to-pydantic

- Added testing for python 3.13
- Fixed RootModel type hint, uses the model type instead of unknown

https://github.com/magicalpuffin/pandas-to-pydantic/pull/11

- v0.1.4, deprecated expand_annotations method, refactor get_columns test cases
- v0.1.3, tooling update configuring pyright and pandas stubs
- v0.1.2, supporting pydantic class inheritance by using issubclass() instead of __base__
- v0.1.1, added fallback using model name in get_model_columns

Now supports more complex Pydantic models such as those with child models or multiple model lists.