Fix Bruschetta typo (#6563)

Fixes https://github.com/flutter/flutter/issues/6561

examples/flutter_gallery/lib/demo/pesto_demo.dart

@@ -555,7 +555,7 @@ class RecipeStep {
 
 final List<Recipe> kPestoRecipes = <Recipe>[
   const Recipe(
-    name: 'Pesto Bruchetta',
+    name: 'Pesto Bruschetta',
     author: 'Peter Carlsson',
     ingredientsImagePath: 'packages/flutter_gallery_assets/pesto/quick.png',
     description: 'Bask in greens this season by trying this delightful take on traditional bruschetta. Top with a dollop of homemade pesto, and season with freshly ground sea salt and pepper.',