[data][llm] fix: remove-no-longer needed guided decoding vllm v0 constraint

[ArthurBook]

Why are these changes needed?

vLLM v1 supports xgrammar and guidance since v0.8.2

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[kouroshHakha]

@ArthurBook thanks, have you confirmed that guided decoding with batch llm works for v1 as well? If so what vllm version have you tried it with?

[kouroshHakha]

kicking off release tests to make sure there is unseen issue: https://buildkite.com/ray-project/release/builds/41125

[ArthurBook]

Hi @kouroshHakha.
Runs fine with vLLM==0.8.5 + xgrammar==0.1.18 backend using vLLMEngineProcessorConfig with engine_args.guided_decoding_backend = "xgrammar".