assume CMake>=3.22 (as documented in the CGAL manual)

Author: lrineau

Installation/lib/cmake/CGAL/CGALConfig.cmake

@@ -2,6 +2,8 @@
 # This file is the CGALConfig.cmake for a header-only CGAL installation
 #
 
+cmake_minimum_required(VERSION 3.22...3.31)
+
 # For CGAL_CreateSingleSourceCGALProgram.cmake
 set( CGAL_REQUESTED_COMPONENTS ${CGAL_FIND_COMPONENTS} )
 
@@ -10,11 +12,7 @@ set(CGAL_LIBRARIES CGAL)
 # Resolve symlinks before extracting the directory so that the subsequent
 # DIRECTORY walk produces a correct CGAL_ROOT (e.g. /lib -> /usr/lib on
 # Arch Linux).  See https://github.com/CGAL/cgal/issues/8521
-if(NOT CMAKE_VERSION VERSION_LESS 3.19)
-  file(REAL_PATH "${CMAKE_CURRENT_LIST_FILE}" _cgal_config_realpath)
-else()
-  get_filename_component(_cgal_config_realpath "${CMAKE_CURRENT_LIST_FILE}" REALPATH)
-endif()
+file(REAL_PATH "${CMAKE_CURRENT_LIST_FILE}" _cgal_config_realpath)
 get_filename_component(CGAL_CONFIG_DIR "${_cgal_config_realpath}" DIRECTORY)
 
 function(cgal_detect_branch_build VAR_NAME)