Integrate gptCache about llmchat

[c0sogi]

Unfortunately, this library does not support redis. Instead, you need to use mysql as a cache, and it only supports 'milvus', 'faiss', 'chromadb', and 'hnswlib' as vector databases.

In my testing with mysql, I found that the library does not support asynchronous operations at all. This means that if multiple users are requesting the cache at the same time, all other users will have to wait for one user to finish until all of them have finished.

[Torhamilton]

Thanks, that was real fast! There is already an open issue for Redis integration zilliztech/GPTCache#271
Let's hope our bet on Redis pays off! I will watch GPTCache