[HANDS-ON BUG] requirements file is outdated

# Describe the bug

The version of pygame in the unit-1 requirements text file is outdated and incompatible with Colab's python version. This results in build errors when installing.
https://github.com/SiamRahman29/hf-deep-rl/blob/main/notebooks/unit1/unit1.ipynb
See the cells after !apt install swig cmake

Can I submit a PR to fix this?

# Material

I used Google Colab.

Start with notebooks/unit1/unit1.ipynb and inspect the cells after `!apt install swig cmake`, then locate the referenced unit-1 requirements text file and its pygame version. Update the dependency so installation works with Colab's Python version, and verify those cells install without build errors.

Written by the indexing model from the issue text.