Fix with pinned filters IndexFilters example on website (#12759)

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changes in the style guide

Author: gwyneplaine

polaris.shopify.com/pages/examples/index-filters-with-pinned-filters.tsx

@@ -191,7 +191,7 @@ function IndexFiltersWithPinnedFiltersExample() {
           allowMultiple
         />
       ),
-      shortcut: true,
+      pinned: true,
     },
     {
       key: 'taggedWith',
@@ -205,7 +205,7 @@ function IndexFiltersWithPinnedFiltersExample() {
           labelHidden
         />
       ),
-      shortcut: true,
+      pinned: true,
     },
     {
       key: 'moneySpent',