Prevent unnecessary clone

This also ensures that the address resolver actually keeps state.
Otherwise it was cloned before each resolution, resulting in it never
keeping the resolved addresses.

Signed-off-by: Jacob Kiers <code@kiers.eu>

src/servers/protocol/tcp.rs

@@ -72,21 +72,17 @@ async fn accept(inbound: TcpStream, proxy: Arc<Proxy>) -> Result<(), Box<dyn std
                 "No upstream named {:?} on server {:?}",
                 proxy.default_action, proxy.name
             );
-            return process(
-                inbound,
-                proxy.upstream.get(&proxy.default_action).unwrap().clone(),
-            )
-            .await;
+            return process(inbound, proxy.upstream.get(&proxy.default_action).unwrap()).await;
             // ToDo: Remove unwrap and check default option
         }
     };
 
-    return process(inbound, upstream.clone()).await;
+    return process(inbound, &upstream).await;
 }
 
 async fn process(
     mut inbound: TcpStream,
-    upstream: Upstream,
+    upstream: &Upstream,
 ) -> Result<(), Box<dyn std::error::Error>> {
     match upstream {
         Upstream::Ban => {