[BugFix] Throw a runtime error for quantized models & inference=VLLM

[kaisopos]

Description

Throw a runtime error when instantiating a {judge, evaluation, inference} config that includes a "BitsAndBytes" quantized model and a VLLM inference engine. I am aware this does NOT cover all possible use cases (users may use an inference engine directly without a config) but my hope is that it covers most cases.

Related issues

Fixes # (issue)

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