Remove upsell task Sell your course with WooCommerce task from Sensei core and deprecate class

[Imran92]

As part of changes we are making in Sensei Home tasks and the new Tours, we have introduced a new task (#7486) "Sell your course with Sensei Pro" which replaces the existing upsell "Sell your course with WooCommerce" task. "Sell your course with WooCommerce" points to a different URL now and is moved to Sensei Pro (https://github.com/Automattic/sensei-pro/pull/2557).

We'll remove the usage of this task's class and deprecate it as part of this issue