Fix shadow endpoint when ending with slash

[PH4NTOMiki]

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This should fix #3718 issue with shadow endpoint.
If there is something I'm missing with this PR please say.

[changeset-bot]

🦋 Changeset detected

Latest commit: 7193b60

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@sveltejs/kit	Patch

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[PH4NTOMiki]

@benmccann should this be merged since you approved it?

[benmccann]

sure. I was waiting to see if anyone else wanted to take a look, but I'll go ahead and merge it since it's been a little while