[companion] Fix request-response protocols backpressure mechanism (#7276)

* Replace request-response incoming requests queue with `async-channel`

* Fix unused imports

* Fix channel type in tests

* Fix channel type in tests (part 2)

* Fix unused imports

* update lockfile for {"substrate"}

---------

Co-authored-by: parity-processbot <>

polkadot/node/network/protocol/src/request_response/incoming/mod.rs

@@ -16,10 +16,7 @@
 
 use std::marker::PhantomData;
 
-use futures::{
-	channel::{mpsc, oneshot},
-	StreamExt,
-};
+use futures::{channel::oneshot, StreamExt};
 
 use parity_scale_codec::{Decode, Encode};
 
@@ -208,7 +205,7 @@ pub struct OutgoingResponse<Response> {
 ///
 /// Takes care of decoding and handling of invalid encoded requests.
 pub struct IncomingRequestReceiver<Req> {
-	raw: mpsc::Receiver<netconfig::IncomingRequest>,
+	raw: async_channel::Receiver<netconfig::IncomingRequest>,
 	phantom: PhantomData<Req>,
 }