Mention create_symlink now working in Windows on "Running Other Programs" page

"What's new in CMake" says that as of 3.13, -E create_symlink works on Windows https://cliutils.gitlab.io/modern-cmake/chapters/intro/newcmake.html

The bottom of "Running Other Programs" still says it doesn't https://cliutils.gitlab.io/modern-cmake/chapters/basics/programs.html