ipsets and iptables rules should be clean up on flush()

[bechampion]

Feature Request

Upon experiment deletion (in this case a network experiment (qdisc + iptables + ipset) , only the qdisc is deleted. I would like it if the iptables rule and ipset x2 are also removed , so we leave the pod in the same state we found it.

There's a flush() that does this for qdiscs https://github.com/chaos-mesh/chaos-mesh/blob/master/pkg/chaosdaemon/tc_server.go#L308-L321 , but we would need also an entrypoint for the iptables that deal with that class and the ipsets the iptables refers to.

[nioshield]

@STRRL I'm interested in fixing this problem, can you please assign it to me? Thank you!