E2E Testing the Greenwood website (with GitHub Actions)

[thescientist13]

Coming out of #500 / #515 (and #495), and as with most apps, it is clear that certain features of Greenwood would benefit from being tested in a browser and just what can be determined from reading the generated HTML. Actually clicking links and confirming routing works, would be much better suited to being executed by a real browser.

It would be great to get this run as a GitHub Action, either as part of CI or at the least when merged into master. Not sure what good testing tools we could use, maybe Cypress or Web Test Runner?

Doesn't need to be much, but would be nice to have some basic peace of mind.

[thescientist13]

Probably want to add this to the test suite - #909

[thescientist13]

another case to cover - #932

[thescientist13]

More router bugs

• hash navigation fails to navigate to correct heading/page with staticRouter #936
• deeply nested direct hash link breaks the router if pathname not already present #1026

[thescientist13]

Not our bug for once, but this also happened lately - #1068

[thescientist13]

Started up a little proof of concept using Playwright, for anyone interested in working on this.
https://github.com/thescientist13/playwright-demo