commit 6b3b0a17c6 introduced a check for
the PID file before attempting to move the PID to a new scope.
This is still vulnerable to TOCTOU race condition though, since the
PID file or the PID can be removed/killed after the check was
successful but before it was used.
Closes: https://github.com/containers/podman/issues/12065
[NO NEW TESTS NEEDED] it fixes a CI flake
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>