Implement a hook useInterval(callback, delay) that repeatedly calls a given function at a specified interval.

The hook should:

• Accept a callback function and a delay in milliseconds.
• Return a cleanup function to stop the interval.
• Automatically handle updating the interval if the callback changes.
• Properly clear the interval when no longer needed.

Example

let count = 0;
const stop = useInterval(() => { count += 1; }, 1000);

setTimeout(() => {
  stop(); // stops the interval
}, 5000);