Update prompt.gjs (#1893)

Author: NullVoxPopuli

apps/tutorial/public/docs/12-loading-patterns/1-keeping-latest/prompt.gjs

@@ -52,7 +52,7 @@ export default class Demo extends Component {
       {{else}}
         {{! This block only matters during the initial request }}
 
-        {{#if this.rejest.isRejected}}
+        {{#if this.request.isRejected}}
           error loading initial data!
         {{else}}
           <pre> ... loading ... </pre>