Use conversation history with MultiRetrievalQAChain

[evenfrost]

Checked

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Feature request

It would be great to make it possible to use multiple retrievers, LLM, and conversation history together.

Motivation

Currently, when using MultiRetrievalQAChain.fromLLMAndRetrievers, you can provide an LLM and multiple retrievers for context. If there was a possibility to add a conversation/chat history to this flow, it could help further understand the context, especially in cases where there was a previous conversation between a user and a human agent/bot.

Proposal (If applicable)

No response