add a separate "with-jest-jsdom" example

[VanTanev]

Jest without JSDOM is simpler to run and does not require undici patching.

Closes #99

[kettanaito]

Thanks for opening this, @VanTanev! I left a few comments, will address them once I have a minute.

[kettanaito]

I renamed the example, added it to the CI, elaborated more on what and why to do in its README. This should be good now, let's see the tests!

[VanTanev]

Oops, I guess removing ts-node was too optimistic - although it did run OK locally?

[kettanaito]

@VanTanev, it ran okay locally because other examples used ts-node, I suppose. On CI, each example only installs its own dependencies.

[VanTanev]

@kettanaito Thank you!