Replace Coursework Planner Setup video with updated version

There's a link to a video to set up the coursework planner at the bottom of [this page](https://programming.codeyourfuture.io/user-data/prep/#set-up-planner)
It's causing some confusion due to the usage of Kamino - which in most cases we don't need any more. We can replace this with a new video showing the use of the new "Clone" button.