chore: remove top level promise await behavior

[gtm-nayan]

Closes #10106

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Latest commit: 7a17acd

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[benmccann]

It looks like maybe the generated types don't allow void as a return type for load. Not sure what we think about whether that should be allowed or not. @dummdidumm?

[dummdidumm]

Having fixed two tests, and seing that it's a bit tough to ergonomically do this, I'm wondering if we should provide the function we used previously as a helper that you can import?

[Rich-Harris]

the site deploy failure looks like a real bug, though i'm a bit confused by it

[Rich-Harris]

oh it's because the site has a load that returns top-level promises 🤦 fixed

[Rich-Harris]

this LGTM — should it still be draft, or can we merge?

[dummdidumm]

I think we can merge, AFAIK it was in draft Mode because of type failures which I fixed

[benmccann]

oh wait. this one needs a changeset still