systemtest/010-inspect.bats: require only PATH
systemtest/010-inspect.bats: require only PATH

The "inspect: env" test started failing since the environment in the
`fedora:latest` image has changed.  Hence, only check for `PATH` in
the image's environment which is a defacto standard.

Signed-off-by: Valentin Rothberg <c8d7c67387706f1534261b1aba83f5c355c00ff5@redhat.com>

mtrmac/skopeo,mtrmac/skopeo,mtrmac/skopeo