- Add `close` and `disconnect` in `Host`
- Add `close` and `close_peer` in `Network`
- Change `IListener.close` to async, to await for server's closing
- Add factories for security transports, and modify `HostFactory`
- Dedup `perform_test_from_obj` and the test cases used in both
`test_floodsub` and `test_gossipsub_backward_compatibility.py`.
Therefore, they are put in the standalone file
`tests/pubsub/floodsub_integration_test_settings.py`. The functions
and testcases are imported from there then.
- IMO still need a refactor on the tests. There are still some duplicate
code.