Update README file

[dioloib]

Hello, I have recently reproduced your work and successfully obtained the results you provided. However, I encountered several issues during the reproduction, so I have corrected some errors in the README according to my reproduction steps:

1. Adding the recommended Python version: Python <= 3.10. The corresponding version of faiss cannot be installed in Python 3.11.
2. Corrected some spelling errors. Like 'pip install requirements.txt'
3. FAISS installation: FAISS should be installed using 'conda install -c conda-forge faiss-gpu=1.7.2'. In fact, the original README's method of installing faiss with requirements.txt is problematic, leading to high ppl reproduction in knnlm.
4. Adding missing dependency: The requirements were missing accelerate, which has been added.
5. Adding explanations for steps 2 and 3.
6. Adding a parameter to avoid errors: Add a parameter --dstore_size 116988150 to steps 3 and 4 to avoid errors.