Changes to requirements.txt and README.md

[akshayvkt]

1. Added google-generativeai to requirements.txt to prevent the below error when running maestro-anyapi.py

 import google.generativeai as genai  # type: ignore
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
ModuleNotFoundError: No module named 'google.generativeai'

2. Updated README.md to reflect the new filepath for
   requirements.txt