Clippy issue

crates/client/src/client.rs

@@ -155,7 +155,7 @@ impl Client {
                     tokio::select! {
                         Some(msg) = send_to_socket.recv() => {
                             if let Request::Request(sub) = &msg {
-                                if subscriptions.get(&sub.subscription_id).is_some() {
+                                if subscriptions.contains_key(&sub.subscription_id) {
                                     log::warn!("{}: Already subscribed to {}", url, sub.subscription_id);
                                     continue;
                                 }