Feature Add more pizzas

## Dependent ticket: complete and merge #9 before starting this ticket

**Instructions:**

In the `` component, create a new function named `orderOne`. The `orderOne` function doesn't take any parameters and should use the `setOrders` function to increment the `orders` state variable by 1. Then, add a `onClick` handler to the Add `` that calls the `orderOne` function when it's being clicked.

**Test:**

When the Add button is clicked, the number of pizzas increases by 1