Added trailing button to delete cart item in provider_shopper App (#571)

provider_shopper/lib/screens/cart.dart

@@ -46,6 +46,12 @@ class _CartList extends StatelessWidget {
       itemCount: cart.items.length,
       itemBuilder: (context, index) => ListTile(
         leading: Icon(Icons.done),
+        trailing: IconButton(
+          icon: Icon(Icons.remove_circle_outline),
+          onPressed: () {
+            cart.remove(cart.items[index]);
+          },
+        ),
         title: Text(
           cart.items[index].name,
           style: itemNameStyle,