[Misc] Add w8a8 block fp8 tune script

[DefTruth]

Adapted from https://github.com/sgl-project/sglang/blob/main/benchmark/kernels/quantization/tuning_block_wise_kernel.py. Thank you @HandH1998

• usage

# Tune triton w8a8 block fp8 for DeepSeek-V3/DeepSeek-R1:
python3 benchmark_w8a8_block_fp8.py --tp-size 8 --input-type fp8
# Then copy then configs to vllm/model_executor/layers/quantization/utils/configs

[github-actions]

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[DefTruth]

reopen ai #15126, fix DCO.