revert: fix: disable keepNames in vite:esbuild (fixes #9164)

[TrulyBright]

This reverts commit e6f3b02 to fix #13727.

Description

It is possible for esbuild to rename symbols even if it is not minifying.
But in order for tree-shaking to properly work, we disabled keepNames in vite:esbuild phase, which let renaming. One proof of concept shows it actually renames and causes a problem like in #13727.
Therefore we should let keepNames be respected again in vite:esbuild phase.

Additional context

Tree-shaking is about file size while keepNames is about the real logic that matters. I think it's an enough reason to revert a commit.

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What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

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[illegalnumbers]

Is anyone looking at this?