fix: Set element's value attribute to default empty string if nothing is provided

[asvsfs]

fix: https://github.com/sveltejs/svelte/issues/4467

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Tests

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[Conduitry]

What issue is this related to? What is this intended to fix?

[asvsfs]

What issue is this related to? What is this intended to fix?

@Conduitry Forgot to mention ! it is related to #4467

[benmccann]

can you rebase against master and make sure npm run lint passes? we just updated our eslint config to allow only single quotes

[stale[bot]]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[benmccann]

Just a reminder that this PR would need a rebase

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[dummdidumm]

Looking at the compiler output, I think we should either remove the input.value = .. assignmed that happens in c() or adjust that one instead to use the set_input_value method. The way it's now is setting the value two times essentially.