gguf Mixtral instruct finetune chatml DPO RLHF gpt4 synthetic data distillation en dataset:teknium/OpenHermes-2.5 base_model:mistralai/Mixtral-8x7B-v0.1 base_model:quantized:mistralai/Mixtral-8x7B-v0.1 license:apache-2.0 region:us