fix: Update Cache-Control headers for static resources in router

[HynoR]

What this PR does / why we need it?

参考推荐做法，打包好的vue asset通常文件名有hash, 可视为永远不变，加上immutable 让浏览器完全缓存，避免刷新验证。

Summary of your change

给 asset 下的文件都加上 immutable cache 标记

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• Made sure tests are passing and test coverage is added if needed.
• Made sure commit message follow the rule of Conventional Commits specification.
• Considered the docs impact and opened a new docs issue or PR with docs changes if needed.

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[zhengkunwang223]

/lgtm