fix custom attribute value support

packages/core/tests/bubble_error.rs

@@ -20,7 +20,9 @@ fn app(cx: Scope) -> Element {
 fn bubbles_error() {
     let mut dom = VirtualDom::new(app);
 
-    let _edits = dom.rebuild().santize();
+    {
+        let _edits = dom.rebuild().santize();
+    }
 
     dom.mark_dirty(ScopeId(0));