Set correct $page.status when using enhance and result is of type 'error'

[PatrickG]

Fixes #8072

I wanted to create a +error.svelte in test/apps/basic/src/routes/actions/enhance for this test, but somehow it is not mounted in the "js"-test. I also tried to put it in test/apps/basic/src/routes/actions, that also didn't work.
Furthermore, I've tried to debug with playwright debug, but couldn't find any reason why it does not work.

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@sveltejs/kit	Patch

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[dummdidumm]

Thank you! (type check error is unrelated)