chore: upgrade rollup 3.20.0

[sun0day]

Description

This PR's main purpose is to fix #11911, also I add a extra test case to test CSS files built consistency.

Additional context

refs rollup/rollup#4912

3.18.0 -> 3.20.0 changelog see: https://github.com/rollup/rollup/blob/master/CHANGELOG.md

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What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

Before submitting the PR, please make sure you do the following

• Read the Contributing Guidelines.
• Read the Pull Request Guidelines and follow the PR Title Convention.
• Check that there isn't already a PR that solves the problem the same way to avoid creating a duplicate.
• Provide a description in this PR that addresses what the PR is solving, or reference the issue that it solves (e.g. fixes #123).
• Ideally, include relevant tests that fail without this PR but pass with it.

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[patak-dev]

Awesome cross-project work 👏🏼

[sun0day]

Awesome cross-project work 👏🏼

Thanks. Try ecosystem-ci ??

[patak-dev]

/ecosystem-ci run

[vite-ecosystem-ci]

📝 Ran ecosystem CI: Open

suite	result
astro	❌ failure
histoire	❌ failure
iles	✅ success
ladle	✅ success
laravel	✅ success
marko	✅ success
nuxt	✅ success
previewjs	✅ success
qwik	✅ success
rakkas	✅ success
sveltekit	✅ success
vite-plugin-ssr	✅ success
vite-plugin-react	✅ success
vite-plugin-react-pages	✅ success
vite-plugin-react-swc	✅ success
vite-plugin-svelte	✅ success
vite-plugin-vue	✅ success
vite-setup-catalogue	✅ success
vitepress	✅ success
vitest	✅ success
windicss	✅ success

[sapphi-red]

Thank you!