We were grepping for 'hello world', and in the namespace we would
match on 'hello world', and outside, on 'echo "hello world"'. When
the condition check was fixed, the test gave a false positive.
systemd-run -p LogNamespace=foobar echo "hello world"
journalctl --namespace=foobar --sync
-journalctl --namespace=foobar >/tmp/hello-world
-journalctl >/tmp/no-hello-world
+journalctl -o cat --namespace=foobar >/tmp/hello-world
+journalctl -o cat >/tmp/no-hello-world
-grep "hello world" /tmp/hello-world
-! grep "hello world" /tmp/no-hello-world
+grep "^hello world$" /tmp/hello-world
+grep "^hello world$" /tmp/no-hello-world && { echo 'unexpected success'; exit 1; }
systemd-analyze log-level info