Authentication of PeerIds in authority discovery records (#10317)

* Consolidating test and production code

* Signing/verifying authority discovery records with PeerId

Unsigned records cannot be rejected yet, they just produce
a warning in the log.

* Upgrading to libp2p 0.40

* libp2p::identity and sp_core::crypto Ed25519 are compatible

* Rejecting authority records unsigned by peer id can be configured

* Fixes based on review comments

* No command-line argument needed

* info was still too much spam in the logs

* Added tests for both strict and loose validation

* Fixing based on review comments

* Pierre preferred a signing method

* Ooops, I need to slow down

* Update bin/node/cli/src/service.rs

* Reexport libp2p crypto used in sc-network

* Added proto3 compatibility tests. And import noise.

Co-authored-by: Bastian Köcher <bkchr@users.noreply.github.com>

substrate/client/authority-discovery/README.md

@@ -1,4 +1,4 @@
-Substrate authority discovery.
+# Substrate authority discovery
 
 This crate enables Substrate authorities to discover and directly connect to
 other authorities. It is split into two components the [`Worker`] and the
@@ -6,4 +6,4 @@ other authorities. It is split into two components the [`Worker`] and the
 
 See [`Worker`] and [`Service`] for more documentation.
 
-License: GPL-3.0-or-later WITH Classpath-exception-2.0
+License: GPL-3.0-or-later WITH Classpath-exception-2.0