feat: several fixes & updates

[akashsaravanan-georgian]

• Update setup.py to use latest versions of transformers, pandas, scikit-learn, scipy and accelerate.
• Add importlib-metadata as there was a dependency error without it.
• Add a .gitignore file
• Add a note to the example notebook to address Failed to import transformers.trainer because of the following error (look up to see its traceback): module 'numpy.linalg._umath_linalg' has no attribute '_ilp64' #71
• Update test configuration to reduce the maximum token length - this speeds up the testing and also prevents certain models with lower sequence lengths from throwing an error.