8. Arrays: Silver challenge solution

[Igor]

for index in 0..<(toDoList.count / 2) {
    let indexToSwap = (toDoList.count - 1) - index
    let itemToSwap = toDoList[indexToSwap]
    
    toDoList[indexToSwap] = toDoList[index]
    toDoList[index] = itemToSwap
}