A couple of weeks ago I setup a full node to test Polkadot. Node fully synced. Test ended, and I turned off the node. After 10 days or so of my node not existing, I keep receiving a lot of traffic on port 30333. Not a big deal at my end, but I imagine nodes sending those requests could probably be using their resources more effectively. My former node is not showing up on telemetry. Is there a way to remove a once-existing node from the network?