vcpkg uses UWP triplet in WinUI on desktop projects

[sylveon]

Describe the bug
When creating a WinUI on Desktop project, vcpkg will use the arch-uwp triplet instead of arch-windows triplet.

Environment

• OS: Windows
• Compiler: Visual Studio 16.9 Preview 2

To Reproduce
Steps to reproduce the behavior:

1. Create a new C++ WinUI on desktop project (using https://marketplace.visualstudio.com/items?itemName=Microsoft-WinUI.WinUIProjectTemplates)
2. Run vcpkg install fmt:x86-windows
3. Try to #include <fmt/format.h> in the project
4. Observe include error

Expected behavior
vcpkg looks up in the desktop triplet for libraries.

Additional context
The file isn't found because vcpkg thinks it is in a UWP project when it is not in a UWP project, so it will lookup for libraries in the UWP triplet, in which fmt isn't installed.

[soumyamahunt]

I think this is related to #15409, there already is a PR #15410 that should fix this issue.

[sylveon]

That indeed seems like it, thanks!