server: store containers state on disk

Signed-off-by: Antonio Murdaca <runcom@redhat.com>

server/sandbox_stop.go

@@ -52,6 +52,7 @@ func (s *Server) StopPodSandbox(ctx context.Context, req *pb.StopPodSandboxReque
 				return nil, fmt.Errorf("failed to stop container %s in pod sandbox %s: %v", c.Name(), sb.id, err)
 			}
 		}
+		s.containerStateToDisk(c)
 	}
 
 	resp := &pb.StopPodSandboxResponse{}