[Hotfix] solve fp8 w8a8 ci test fail

[BBuf]

Motivation

Modifications

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[qeternity]

This commit has broken loading of older Marlin packed models.

KeyError: 'model.layers.0.mlp.gate_up_proj.B'

Looking into it now.

[qeternity]

Ok so this is actually related to the deprecation of the SGLang types, which now correctly passes the check_marlin_supported check in GPTQMarlinConfig. Early Marlin reference code set the model config quant method to gptq with flags like is_marlin_format. So now that we are using vllm.scalar_type.ScalarType instead of sglang.srt.layers.quantization.utils.ScalarType the type check passes, and causes this error (previously the type check failed, forcing the Marlin config usage).

Changing the model config to marlin quant method resolves this.

[qeternity]

Not sure if we want to fix this, or just have people change older configs, but PR here: #4675. Feel free to close it if out of scope.