Convert navigating the PB UI with the keyboard Nightwatch test to a functional JS test under PHPUnit

We currently have Nightwatch tests up and running again. The keyboard-based navigation support in Nightwatch is superior to what we can do in Mink / FunctionalJavaScript tests with PHPUnit.

I think this will probably eventually be Closed (won't fix) as we'll likely convert the Nightwatch tests to Playwright in 📌 Rewrite Nightwatch tests as Playwright Active .

Great to hear that new and superior solutions are being implemented, like Playwright here and Cypress elsewhere. The Drop is Always Moving!