Modules: Tolerate CMAKE_EXECUTE_PROCESS_COMMAND_ERROR_IS_FATAL

Capture `execute_process` calls' `RESULT_VARIABLE`.

We don't actually need to check the result as we presume the existing
logic is already adequate, and sometimes programs return non-zero values
as result of valid query.  I.e. this is a "safe" way to broadly protect
these scripts.

Issue: #27782

Modules/UseJava/Symlinks.cmake

@@ -13,6 +13,7 @@ if (UNIX AND _JAVA_TARGET_OUTPUT_LINK)
         execute_process(
             COMMAND ${LN_EXECUTABLE} -sf "${_JAVA_TARGET_OUTPUT_NAME}" "${_JAVA_TARGET_OUTPUT_LINK}"
             WORKING_DIRECTORY ${_JAVA_TARGET_DIR}
+            RESULT_VARIABLE _result_symlink_creation
         )
     else ()
         message(SEND_ERROR "FATAL: Can't find _JAVA_TARGET_OUTPUT_NAME")