message: [CMake] Fix find_python_libs_windows
  Exporting PYTHON_INCLUDE_DIR to the Python scope somehow got lost in my
  last change. Add it back again. This should fix the Windows bot!
diff: @@ -191,6 +191,7 @@ function(find_python_libs_windows)
  set(PYTHON_EXECUTABLE ${PYTHON_EXE} PARENT_SCOPE)
  set(PYTHON_LIBRARY ${PYTHON_LIB} PARENT_SCOPE)
  set(PYTHON_DLL ${PYTHON_DLL} PARENT_SCOPE)
  + set(PYTHON_INCLUDE_DIR ${PYTHON_INCLUDE_DIR} PARENT_SCOPE)
  set(PYTHONLIBS_VERSION_STRING "${PYTHONLIBS_VERSION_STRING}" PARENT_SCOPE)
  set(PYTHON_VERSION_STRING ${PYTHON_VERSION_STRING} PARENT_SCOPE)
  set(PYTHON_VERSION_MAJOR ${PYTHON_VERSION_MAJOR} PARENT_SCOPE)
  