Build a String Inverter

In this lab, you will build a simple string inverter that reverses the characters of a given string. For example, `"hello"` should become `"olleh"`. **Objective:** Fulfill the user stories below and get all the tests to pass to complete the lab. **User Stories:** 1. You should create a function named `reverseString` that takes a string as an argument. 2. The function should return the reversed string.