Jest testing

[zZHorizonZz]

Description

I'm proposing to add potentially better support for testing with Jest, if possible, or add a section to the official documentation about testing. Currently, I was able to make Jest work with Material Web Components in Next.js, but there's a lot of configuration involved just to get it to function. In particular, there seem to be two methods used: matchMedia and attachInternals. I was able to find a workaround for matchMedia, which seems more likely to be a problem with Jest itself (https://jestjs.io/docs/manual-mocks#mocking-methods-which-are-not-implemented-in-jsdom). However, there's also the attachInternals method, which requires creating a prototype. I found a solution that works, but as the author suggests, I don't think this is the correct way to implement it (https://stackoverflow.com/questions/77512630/what-is-the-correct-way-to-test-a-next-js-react-app-that-uses-the-latest-version).