fix: check for publicDir before checking if it is a parent directory

[schelmo]

Description

This tries to fix #16034 and adds a condition if publicDir is truthy

Additional context

does this needs a test? i couldn't find tests with publicDir set to false, and i couldn't figure out how to set it up.

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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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[sapphi-red]

This was working in pre-5.1.0 because normalizePath('') is '.'. ea5fdeb changed normalizePath('') into ''.

[miken32]

@sapphi-red thanks for the quick approval; when can we expect to see a 5.1.5 5.1.6 release with this fix?

[sapphi-red]

I guess in a week.

[sapphi-red]

/ecosystem-ci run

[vite-ecosystem-ci]

📝 Ran ecosystem CI on b59ef7a: Open

suite	result	latest scheduled
analogjs	❌ failure	❌ failure

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