CMake Error: GoogleTest source folder not found

[Ceaser626]

CMake Error at test/CMakeLists.txt:54 (MESSAGE):
GoogleTest source folder not found

Hi Niederberger,
I cloned the project on Windows and used vcpkg to install all the required packages, including Gtest. But still, I encountered the above error when building the project. If you can give me a hint, it would be helpful!