fix: removed .then() handler

frontend/app_flowy/packages/flowy_infra_ui/lib/widget/dialog/styled_dialogs.dart

@@ -21,11 +21,8 @@ extension IntoDialog on Widget {
         child: this,
       ),
       context,
-    ).then(
-      (value) {
-        dialogFocusNode.dispose();
-      },
     );
+    dialogFocusNode.dispose();
   }
 }