KWSys 2025-03-25 (6a109a7b)

Code extracted from:

    https://gitlab.kitware.com/utils/kwsys.git

at commit 6a109a7b7e7985b39d7dc22c6515888b2921cf90 (master).

Upstream Shortlog
-----------------

Brad King (2):
      a3f10d75 Drop unused code for compatibility with CMake < 2.6
      f555ff3a Require CMake 3.13 or higher, enable policies through 3.31

Peter Kokot (2):
      03be1fd7 Replace CMAKE_COMPILER_IS_GNUCXX with CMAKE_CXX_COMPILER_ID
      1a2e54be CTest: Replace deprecated TEST_INCLUDE_FILE with TEST_INCLUDE_FILES