Write additional tests

99% of the work here is done, still having a few troubles with the waitForElementVisible function not behaving as I would expect it to.

@lrwebks I'd more like the test classes to be named according what they do - as it's very specific here, at least for tests/src/FunctionalJavascript/BetterUserAccountsFormTest.php

All green!! 🎉🎉🎉

Automatically closed - issue fixed for 2 weeks with no activity.