fix(plugin-legacy): disable babel.compact when minify is disabled

[sapphi-red]

Description

compact was set to true always.
This PR changes it to false when build.minify is false.

It might be slightly faster when compact is true than false. So ones who is setting build.minify to false with intention to reduce build time will get a negative effect from this change.

I tested this by setting build.minify to false at playground/legacy/vite.config.js.

close #8180

Additional context

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What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

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