Add an extra button for "Supplements" in course training page

Currently, when managers enter My Classroom, they click the Resume button and go straight into the training section. This causes them to miss out on supplements, since these are only visible on the course page, which they typically do not visit.

To ensure managers are aware of the available supplements, we will display a secondary button inside the training page, which opens up a modal with a list of all the supplements, which will open in a new page, ensuring training is not interrupted.