CMake installation rules use wrong path for package config version file.

[Q-Minh]

Hi, thank you for your contribution.

I noticed that the installation rule for the package config version file found here uses ${CMAKE_BINARY_DIR} instead of ${CMAKE_CURRENT_BINARY_DIR}, which causes my CMake installation (which depends on cpp-sort) to fail, due to not being able to find cpp-sort-config-version.cmake. I'm guessing the call to install here silently fails to put cpp-sort-config-version.cmake in the destination. This is an extremely simple fix, simply use ${CMAKE_CURRENT_BINARY_DIR}.