Fix looking for commands with GNU make 4.2.1
Fix looking for commands with GNU make 4.2.1

Before https://git.savannah.gnu.org/cgit/make.git/commit/job.c?h=4.3&id=1af314465e5dfe3e8baa839a32a72e83c04f26ef ,
make was incorrectly trying to avoid running a shell for (command -v).
Use the workaround recommended in https://savannah.gnu.org/bugs/index.php?57625 .

Signed-off-by: Miloslav Trmač <9c008e38982a5397deb855345fb164f0558459ae@redhat.com>

mtrmac/skopeo,mtrmac/skopeo,mtrmac/skopeo