remove convo tag when we invalidate it

llarp/service/endpoint.cpp

@@ -924,6 +924,7 @@ namespace llarp
           return false;
         {
           LogWarn("invalidating convotag T=", frame.T);
+          RemoveConvoTag(frame.T);
           util::Lock lock(m_state->m_SendQueueMutex);
           m_state->m_SendQueue.emplace_back(
               std::make_shared<const routing::PathTransferMessage>(f, frame.F), p);