Previous PR #12394 tried to address this, but made a mistake:
containers that have just exited do not move to the Exited state
but rather the Stopped state - as such, the code would never have
run (there is no way we start `podman kill`, and the container
transitions to Exited while we are doing it - that requires
holding the container lock, which Kill already does).
Fix the code to check Stopped as well (we omit Exited entirely
but it's a cheap check and our state logic could change in the
future). Also, return an error, instead of exiting cleanly - the
Kill failed, after all. ErrCtrStateInvalid is already handled by
the sig-proxy logic so there won't be issues.
[NO NEW TESTS NEEDED] This fixes a race that I cannot reproduce
myself, and I have no idea how we'd repro in CI.
Signed-off-by: Matthew Heon <mheon@redhat.com>
c77691f06f