Update 'README.md'

README.md

@@ -47,10 +47,12 @@ The goal of this exercise is to know how to create and test a class.
 ## Part 4 - Product as an ArrayList - BONUS
 The goal of this exercise is to change the `products` array in the `Cart` class to an ArrayList.
   1. In the `CartTest`, change the `products` array to an `ArrayList`
+  
     ```java
       ArrayList<Product> products = new ArrayList();
       products.add(new Product("Shirt", 15.01));
     ```
+    
   2. Add this test to the `CartTest` class
   ```java
     @Test