fix remaining core tests

packages/core/tests/task.rs

@@ -30,7 +30,7 @@ async fn it_works() {
 
     let mut dom = VirtualDom::new(app);
 
-    let _ = dom.rebuild(&mut dioxus_core::NoOpMutations);
+    dom.rebuild(&mut dioxus_core::NoOpMutations);
 
     tokio::select! {
         _ = dom.wait_for_work() => {}