Please supplement comparison between Faiss GPU-based and RAFT GPU-based methods

[Melon-Water]

Knowhere 2.1.0 Beta Pre-release information contains comparison between RAFT GPU-based IVF methods and other CPU-based methods(ivf-series methods seem to be CPU-based).

Looking forward to seeing the comparison between Faiss GPU-based ivf-series and RAFT GPU-based ivf-series methods.