Fix old test: wrapper was not in scope

packages/@ember/-internals/glimmer/tests/integration/components/curly-components-test.js

@@ -2501,7 +2501,7 @@ moduleFor(
           },
           value: null,
         }),
-        template: '<div id="inner-value">{{wrapper.content}}</div>',
+        template: '<div id="inner-value">{{this.wrapper.content}}</div>',
       });
 
       let expectedBacktrackingMessage = backtrackingMessageFor('content', '<.+?>', {