content: Swiper React modules documentation is outdated

[sean-perkins]

URL

https://ionicframework.com/docs/react/slides#using-modules

Issue Description

The Pagination and other swiper modules are no longer part of the core swiper package. Instead developers need to import from swiper/modules.

Resource: https://swiperjs.com/swiper-api#using-js-modules

[brandyscarney]

This was resolved by #3806