Add tests for Pizza::Pie#vegetarian so it returns true when pizza has no non-vegetarian toppings and false when any of the toppings are non-vegetarian
Add Pizza::Pie#add_topping to create passing test and allow a user to add a new topping to the toppings ivar for a given Pie
Write failing test for Pizza::Pie#deliver!
Write failing tests for Pizza::Pie#late? so it expects false if the @delivery_time is greater than the current time, and it returns true if the @delivery_time is less than the current time
Change time variables in test from now to delivery time and current time to increase readability