fix logic issue added recently

Author: Ivansete-status

channels/reliable_channel.nim

@@ -137,7 +137,11 @@ proc pruneCompletedChannelReqs(self: ReliableChannel) =
   ## segment doesn't trigger a drop on its own — we wait until siblings
   ## are also accounted for, so the channel-level outcome is decided
   ## from a complete picture.
-  self.pendingMessagingRequests.keepItIf(not it.segmentSendState.isFinal())
+  var channelsWithPending = initHashSet[RequestId]()
+  for entry in self.pendingMessagingRequests:
+    if not entry.segmentSendState.isFinal():
+      channelsWithPending.incl(entry.channelReqId)
+  self.pendingMessagingRequests.keepItIf(it.channelReqId in channelsWithPending)
 
 proc onMessageSent(self: ReliableChannel, messagingReqId: RequestId) =
   ## Invoked from this channel's `MessageSentEvent` listener. Flips