clippy: map -> inspect when original item is returned

Fixing a clippy lints regarding a usage of `map()` instead
of `inspect()`, when original item (closure argument) is returned
from the closure.

scylla-proxy/src/proxy.rs

@@ -750,19 +750,17 @@ impl Doorkeeper {
                 desired_addr
             };
 
-            socket.connect(real_addr).await.map(|ok| {
+            socket.connect(real_addr).await.inspect(|ok| {
                 info!(
                     "Connected to the cluster from {} at {}, intended shard {}.",
                     ok.local_addr().unwrap(),
                     real_addr,
                     shard_preserving_addr.port() % shards
                 );
-                ok
             })
         } else {
-            TcpStream::connect(real_addr).await.map(|ok| {
+            TcpStream::connect(real_addr).await.inspect(|_| {
                 info!("Connected to the cluster at {}.", real_addr);
-                ok
             })
         }
         .map_err(|err| DoorkeeperError::NodeConnectionAttempt(real_addr, err))?;