`utilities.h` includes `known_folders.h`, which is missing from the NuGet package

[sylveon]

As title says, we can't build out of band PSF fixups with the NuGet.

git blamed to 0f35538 which updated utilities.h but did not include known_folders.h in the nuspec (CC @npuvvada)

[riverar]

Can probably cherry-pick from the develop branch in the meantime https://github.com/microsoft/MSIX-PackageSupportFramework/blob/develop/include/known_folders.h

[sylveon]

Yes, that's what I did (+ the dos_paths file)