Similar to sandbox removal, the stop of a sandbox should be a noop if
the sandbox has not been found.
Found during: https://github.com/kubernetes-sigs/cri-tools/pull/1535
Signed-off-by: Sascha Grunert <sgrunert@redhat.com>
so that we cri service don't have to get sandbox controller everytime it
needs to call sandbox controller api.
Signed-off-by: Abel Feng <fshb1988@gmail.com>