updates main.rs, applies default formatting from rustfmt

src/main.rs

@@ -5,7 +5,5 @@ async fn main() {
     let hello = warp::get()
         .map(|| format!("Hello world!"));
 
-    warp::serve(hello)
-        .run(([127, 0, 0, 1], 5309))
-        .await;
-}
+    warp::serve(hello).run(([127, 0, 0, 1], 5309)).await;
+}