Drop broken debug assertion on peer buffer lengths

1b711ed changed it so that we can
enqueue broadcast gossip messages to peers even though their buffer
is full as long as its our `ChannelMessageHandler` doing it. This
broke a debug assertion that the buffer isn't too large when
appending the broadcast message which is simply dropped here.

Found by the `full_stack_target` fuzzer.

Author: TheBlueMatt

lightning/src/ln/peer_handler.rs

@@ -1365,7 +1365,6 @@ impl<Descriptor: SocketDescriptor, CM: Deref, RM: Deref, OM: Deref, L: Deref, CM
 	/// Append a message to a peer's pending outbound/write gossip broadcast buffer
 	fn enqueue_encoded_gossip_broadcast(&self, peer: &mut Peer, encoded_message: MessageBuf) {
 		peer.msgs_sent_since_pong += 1;
-		debug_assert!(peer.gossip_broadcast_buffer.len() <= OUTBOUND_BUFFER_LIMIT_DROP_GOSSIP);
 		peer.gossip_broadcast_buffer.push_back(encoded_message);
 	}