actually make clippy happy

examples/flat_router.rs

@@ -17,7 +17,7 @@ fn main() {
 }
 
 fn app(cx: Scope) -> Element {
-    use_router(cx, &|| RouterConfiguration::default(), &|| {
+    use_router(cx, &RouterConfiguration::default, &|| {
         Segment::content(comp(Home))
             .fixed("games", comp(Games))
             .fixed("play", comp(Play))