[Benchmark] Fix python build error

[Potabk]

What this PR does / why we need it?

When we are using pip install -e ., the entrypoint is pyproject.toml, but there exist an issue toml section missing PosixPath('pyproject.toml') does not contain a tool.setuptools_scm section when using using setuptools_scm and section:[tool.setuptools_scm] is miss, fix https://github.com/vllm-project/vllm-ascend/actions/runs/19548410938/job/55973159872

Does this PR introduce any user-facing change?

How was this patch tested?

• vLLM version: v0.11.0
• vLLM main: vllm-project/vllm@2918c1b

[gemini-code-assist]

Code Review

This pull request correctly fixes a build error that occurs with pip install -e . by adding the necessary [tool.setuptools_scm] section to the pyproject.toml file. The change is straightforward, correct, and effectively resolves the described issue.

[github-actions]

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