Request add an option like --show-toolchain-file to vcpkg

[krishna116]

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Is your feature request related to a problem? Please describe.
When user want to use vcpkg toolchain file, the user should remember where it is, the user must explicitly provide the full-path-file-name. It is not very convenient, for example:

cmake -S . -B build -DCMAKE_TOOLCHAIN_FILE=[path to vcpkg]/scripts/buildsystems/vcpkg.cmake

Proposed solution
if vcpkg can provide a option like "--show-toolchain-file" then it will be much better. for example:

cmake -S . -B build -DCMAKE_TOOLCHAIN_FILE=$(vcpkg --triplet <your-triplet> --show-toolchain-file)

Thanks.

[krishna116]

It has some advantages:
1, the user do not need to remember where the toolchain file it is in the file system.
2, make installed toolchain file relocatable. for example the build process will be in some virtual environment like docker, so the toolchain file can be synchronized with the virtual environment by this option --show-toolchain-file.
3, the path provided by vcpkg may be uniform in various platforms, so the user don't need care about "/path" or "...\path" or "...\\path" and so on.