Add Llama3 support in LLMGraphTransformer

[Ronnie-Leon76]

Checked

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Feature request

Currently, it seems LLMGraphTransformer only supports Mistral and OpenAI's models. Could LLMGraphTransformer be extended to use Llama3?

Motivation

I'm building a GraphRAG system and I would like to leverage Llama3's semantic power to correctly extract and map entities and relationships.

Proposal (If applicable)

No response