fortify: move test_fortify.sh to lib/test_fortify/

This script is only used in lib/test_fortify/.

There is no reason to keep it in scripts/.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Link: https://lore.kernel.org/r/20240727150302.1823750-3-masahiroy@kernel.org


Signed-off-by: Kees Cook <kees@kernel.org>