Get rid of `libp2p` dependency in `sc-authority-discovery` (#5842)

## Issue
#4859 
## Description
This PR removes `libp2p` types in authority-discovery, and replace them
with network backend agnostic types from `sc-network-types`.
 The `sc-network` interface is therefore updated accordingly.

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Co-authored-by: Bastian Köcher <git@kchr.de>
Co-authored-by: command-bot <>
Co-authored-by: Dmitry Markin <dmitry@markin.tech>
Co-authored-by: Alexandru Vasile <60601340+lexnv@users.noreply.github.com>