Update jqUnit docs links to QUnit functions

[jobara]

The current docs for jqUnit point out that the module is based on version 1.x of QUnit, and makes reference to certain functions that no longer exist in the new API.

For example, the documentation for jqUnit.asyncTest mentions that it is a "Direct passthrough for QUnit.asyncTest", with a link to the relevant QUnit function: http://api.qunitjs.com/QUnit.asyncTest/

The issue is that that URL then redirects to QUnit.test, as QUnit.asyncTest no longer exists in API 2.x: https://api.qunitjs.com/QUnit/test

Outside of updating the version of QUnit used by jqUnit (a whole other can of worms), I propose updating the text of the links with a mention that the old version of the API is no longer offered on QUnit's website, or perhaps linking to the Wayback Machine's archived version of that page: https://web.archive.org/web/20160604092138/http://api.qunitjs.com:80/QUnit.asyncTest/

Additional context or notes

Originally filed as FLUID-6423 by @BlueSlug on November 1, 2019.