Automate e2e tests for all examples

[jaridmargolin]

Keeping all examples working as API changes are made is cumbersome. I believe the major pain point here is knowing what needs to updated. Currently, this requires manually running each example and verifying output.

I believe we would be able to greatly increase our confidence that examples are all working as expected by creating very light e2e tests. As a first pass, I purpose we simply check that content gets rendered rather than a RedBox.

This should help us mitigate issues like #351 and #360