Require cmake 3.16 for demo_konsolepart too
konsole already requires cmake 3.16. This gets rid of the following warning: "Your project should require at least CMake 3.16.0 to use FindKF5.cmake".
konsole already requires cmake 3.16. This gets rid of the following warning: "Your project should require at least CMake 3.16.0 to use FindKF5.cmake".