删除torch和torch——npu相关依赖安装

[mikequan0425]

What this PR does / why we need it?

Does this PR introduce any user-facing change?

How was this patch tested?

• vLLM version: v0.11.0
• vLLM main: vllm-project/vllm@83f478b

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[gemini-code-assist]

Code Review

这个 PR 移除了 pyproject.toml 文件中 [build-system].requires 部分的 torch 和 torch-npu 依赖。然而，setup.py 在构建过程中依赖 torch-npu 来查找其安装路径并配置 CMake。因此，这个改动会导致从源码分发包（sdist）构建项目时失败。为了正确移除这些依赖，setup.py 中依赖 torch-npu 的逻辑也需要被相应地修改。

[github-actions]

This pull request has conflicts, please resolve those before we can evaluate the pull request.