[test] Do not create a symlink and just copy the directory

Fixes #18499

Author: dpiparo

roottest/cling/staticinit/CMakeLists.txt

@@ -1,10 +1,5 @@
-if(MSVC)
-  execute_process(COMMAND ${CMAKE_COMMAND} -E copy_directory ${CMAKE_CURRENT_SOURCE_DIR}/ROOT-7775
-                                                             ${CMAKE_CURRENT_BINARY_DIR}/ROOT-7775)
-else()
-  execute_process(COMMAND ${CMAKE_COMMAND} -E create_symlink ${CMAKE_CURRENT_SOURCE_DIR}/ROOT-7775 
-                                                             ${CMAKE_CURRENT_BINARY_DIR}/ROOT-7775)
-endif()
+execute_process(COMMAND ${CMAKE_COMMAND} -E copy_directory ${CMAKE_CURRENT_SOURCE_DIR}/ROOT-7775
+                                                           ${CMAKE_CURRENT_BINARY_DIR}/ROOT-7775)
 
 ROOTTEST_ADD_TEST(ROOT-7775
                   MACRO  execROOT-7775.C