Clean up sc-network (#9761)

* Clean up sc-network

- Avoid using clone() for the Copy type `PeerId`.
- Use `find_map` for `filter_map` and `next`.
- Use `Self`.

* More on Copy types

* Cargo +nightly fmt --all

* More ..

* fmt

* Revert vec![default_notif_handshake_message]

substrate/client/network/src/protocol/notifications/handler.rs

@@ -256,7 +256,7 @@ impl IntoProtocolsHandler for NotifsHandlerProto {
 					Protocol { config, in_upgrade, state: State::Closed { pending_opening: false } }
 				})
 				.collect(),
-			peer_id: peer_id.clone(),
+			peer_id: *peer_id,
 			endpoint: connected_point.clone(),
 			when_connection_open: Instant::now(),
 			events_queue: VecDeque::with_capacity(16),
@@ -463,7 +463,7 @@ impl NotifsHandlerProto {
 	/// is always the same whether we open a substream ourselves or respond to handshake from
 	/// the remote.
 	pub fn new(list: impl Into<Vec<ProtocolConfig>>) -> Self {
-		NotifsHandlerProto { protocols: list.into() }
+		Self { protocols: list.into() }
 	}
 }
 
@@ -552,7 +552,7 @@ impl ProtocolsHandler for NotifsHandler {
 				let (sync_tx, sync_rx) = mpsc::channel(SYNC_NOTIFICATIONS_BUFFER_SIZE);
 				let notifications_sink = NotificationsSink {
 					inner: Arc::new(NotificationsSinkInner {
-						peer_id: self.peer_id.clone(),
+						peer_id: self.peer_id,
 						async_channel: FuturesMutex::new(async_tx),
 						sync_channel: Mutex::new(sync_tx),
 					}),