Update logs + do not downscore peers if WE time out (#1901)

## Issue Addressed

- RPC Errors were being logged twice: first in the peer manager and then again in the router, so leave just the peer manager's one 
- The "reduce peer count" warn message gets thrown to the user for every missed chunk, so instead print it when the request times out and also do not include there info that is not relevant to the user
- The processor didn't have the service tag so add it
- Impl `KV` for status message
- Do not downscore peers if we are the ones that timed out

Other small improvements

beacon_node/eth2_libp2p/src/rpc/handler.rs

@@ -14,7 +14,7 @@ use libp2p::swarm::protocols_handler::{
     KeepAlive, ProtocolsHandler, ProtocolsHandlerEvent, ProtocolsHandlerUpgrErr, SubstreamProtocol,
 };
 use libp2p::swarm::NegotiatedSubstream;
-use slog::{crit, debug, warn};
+use slog::{crit, debug, trace, warn};
 use smallvec::SmallVec;
 use std::{
     collections::hash_map::Entry,
@@ -238,7 +238,9 @@ where
     /// Initiates the handler's shutdown process, sending an optional last message to the peer.
     pub fn shutdown(&mut self, final_msg: Option<(RequestId, RPCRequest<TSpec>)>) {
         if matches!(self.state, HandlerState::Active) {
-            debug!(self.log, "Starting handler shutdown"; "unsent_queued_requests" => self.dial_queue.len());
+            if !self.dial_queue.is_empty() {
+                debug!(self.log, "Starting handler shutdown"; "unsent_queued_requests" => self.dial_queue.len());
+            }
             // we now drive to completion communications already dialed/established
             while let Some((id, req)) = self.dial_queue.pop() {
                 self.pending_errors.push(HandlerErr::Outbound {
@@ -283,8 +285,11 @@ where
         let inbound_info = if let Some(info) = self.inbound_substreams.get_mut(&inbound_id) {
             info
         } else {
-            warn!(self.log, "Inbound stream has expired, response not sent";
-                "response" => response.to_string(), "id" => inbound_id, "msg" => "Likely too many resources, reduce peer count");
+            if !matches!(response, RPCCodedResponse::StreamTermination(..)) {
+                // the stream is closed after sending the expected number of responses
+                trace!(self.log, "Inbound stream has expired, response not sent";
+                    "response" => %response, "id" => inbound_id);
+            }
             return;
         };
 

beacon_node/eth2_libp2p/src/rpc/methods.rs

@@ -392,6 +392,22 @@ impl std::fmt::Display for BlocksByRangeRequest {
     }
 }
 
+impl slog::KV for StatusMessage {
+    fn serialize(
+        &self,
+        record: &slog::Record,
+        serializer: &mut dyn slog::Serializer,
+    ) -> slog::Result {
+        use slog::Value;
+        serializer.emit_str("fork_digest", &format!("{:?}", self.fork_digest))?;
+        Value::serialize(&self.finalized_epoch, record, "finalized_epoch", serializer)?;
+        serializer.emit_str("finalized_root", &self.finalized_root.to_string())?;
+        Value::serialize(&self.head_slot, record, "head_slot", serializer)?;
+        serializer.emit_str("head_root", &self.head_root.to_string())?;
+        slog::Result::Ok(())
+    }
+}
+
 impl slog::Value for RequestId {
     fn serialize(
         &self,