try manual expiration of tags

Datagram.cpp

@@ -138,6 +138,8 @@ namespace datagram
       LogPrint(eLogInfo, "DatagramDestination: expiring idle session with ", ident.ToBase32());
       m_Sessions.erase(ident);
     }
+    m_LocalDestination->CleanupExpiredTags();
+    m_LocalDestination->CleanupUnconfirmedTags();
     ScheduleCleanup();
   }