extension_host: Use the more permissive RelPath constructor for paths from extensions (#38965)

Closes #38922 

Release Notes:

- N/A

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Co-authored-by: Jakub Konka <kubkon@jakubkonka.com>
687e22b4c3Cole Miller committed on 9/27/2025, 1:20:42 PM· committed by GitHubparente13b88e
2 files changedLine totals unavailable