fix(worker): hide "The emitted file overwrites" warning if the content is same

[sapphi-red]

Description

The build error in #10057 was fixed by #15469. This PR suppresses the "The emitted file overwrites" warning by skipping this.emitFile if the filename and the content is same.

If the filename is same but the content is different and the warning happens, then I think the user should configure worker.rollupOptions.output.chunkFileNames.

fixes #10057

Additional context

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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, especially the Pull Request Guidelines.
• 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).
• Update the corresponding documentation if needed.
• Ideally, include relevant tests that fail without this PR but pass with it.

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[patak-dev]

/ecosystem-ci run

[vite-ecosystem-ci]

📝 Ran ecosystem CI on 09ce4e8: Open

suite	result	latest scheduled
nx	❌ failure	❌ failure

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