XPod: doStopPod: call removeFromSandbox with every p.containers
XPod: doStopPod: call removeFromSandbox with every p.containers

Some resource for containers needs to be released before p.sandbox.Shutdown.

Add this patch to call removeFromSandbox with every p.containers
before p.sandbox.Shutdown to release the resource.

Signed-off-by: Hui Zhu <3dff0dee05fafb3e3012a2d92c6bc151ff61663b@hyper.sh>

hyperhq/hyper,laijs/hyperd,hyperhq/hyperd,hyperhq/hyper,gnawux/hyper,gnawux/hyper,hyperhq/hyper,laijs/hyperd,laijs/hyper,hyperhq/hyperd,laijs/hyper,hyperhq/hyperd,laijs/hyperd,gnawux/hyper,laijs/hyper,laijs/hyper,hyperhq/hyper