Fix StrictMode warning

[aralroca]

Using React.StrictMode is throwing this warning:

findDOMNode is deprecated in StrictMode. findDOMNode was passed an instance of ReactSwipe which is inside StrictMode. Instead, add a ref directly to the element you want to reference.

    in ul (created by ReactSwipe)
    in ReactSwipe (created by Carousel)

Should be fixed to allow Concurrent mode in the future React releases.

[Cyberlane]

I will take a look into it, however if you know the issue I would of course be happy to accept a PR. Otherwise, please bare with me, and I will have it resolved as soon as I can.