Substrate companion: Authority discovery multiple peer ids (#4295)

* Substrate companion: Authority discovery multiple peer ids

Authority discovery before had a fixed mapping from `PeerId` to
`AuthorityId`. This wasn't correct, as a `PeerId` can actually map to
multiple `AuthorityId`s. The linked Substrate pr fixes this.

https://github.com/paritytech/substrate/pull/10259

* Update node/network/availability-distribution/src/requester/mod.rs

* Update node/network/collator-protocol/src/validator_side/mod.rs

* Update node/network/statement-distribution/src/tests.rs

* Update guide

* Adapt to Substrate pr

* Update Substrate

polkadot/roadmap/implementers-guide/src/types/network.md

@@ -144,7 +144,7 @@ These updates are posted from the [Network Bridge Subsystem](../node/utility/net
 ```rust
 enum NetworkBridgeEvent<M> {
 	/// A peer with given ID is now connected.
-	PeerConnected(PeerId, ObservedRole),
+	PeerConnected(PeerId, ObservedRole, Option<HashSet<AuthorityDiscoveryId>>),
 	/// A peer with given ID is now disconnected.
 	PeerDisconnected(PeerId),
 	/// Our neighbors in the new gossip topology.

polkadot/roadmap/implementers-guide/src/types/overseer-protocol.md

@@ -567,7 +567,7 @@ enum NetworkBridgeMessage {
     /// `PeerConnected` events from the network bridge.
     ConnectToValidators {
         /// Ids of the validators to connect to.
-        validator_ids: Vec<AuthorityDiscoveryId>,
+        validator_ids: HashSet<AuthorityDiscoveryId>,
         /// The underlying protocol to use for this request.
         peer_set: PeerSet,
         /// Sends back the number of `AuthorityDiscoveryId`s which