tokio-tungstenite dropped connection test

Usage

Open three terminals

1. In terminal 1, cargo run -- debug server
2. In terminal 2, cargo run -- debug client
3. Observe monotonic counter being sent over WebSocket
4. In terminal 3, sudo iptables -A INPUT -p tcp --dport 1337 -j DROP
5. Observe absense of monotonic counter reaching the server
6. Wait...
7. Note how the server never terminates the client's connection.
8. Go ahead and C-c the process in terminal 2 to kill the client.
9. In terminal 3, sudo iptables -D INPUT -p tcp --dport 1337 -j DROP to remove firewall rule