v1.4.1

• Update train connector to allow dynamic columns.
• Provide a clear error message if the user does not return a dataframe from a read or wrangle custom function.
• Remove problematic huggingface test that fails due to rate limiting.
• Provide a clear error message if a user tries to access a model they don't have permission for.
• Add pip install test.
• Remove python 3.7 tests as this is now end of life.
• Add MacOS tests.