Add completed lessons to timeline

[chyku]

DON'T PICK THIS UP
This is here so we can put the information here for when we're working on GLEN Learn:

If you want to use the event timeline, you can create a new class at src/util/Timeline/timeline.js in glen-learn. There's a few examples in there; just extend the TimelineEvent class and pass whatever data you'd like via the meta field (in this case, it sounds like the custom lesson name, and a date?). Then, in your application code you can do something like:

const glenLearnProfile = useGlenLearnProfile();
glenLearnProfile.addTimelineEvent(new MyCustomEvent(lessonName, date))

To display the event on the timeline screen in the app you can update: src/pages/GlenLearn/AdminDashboard/DashboardForUser/Timeline/Timeline.js (you'll want to update the itemForEvent variable and add your new case). Note that the timeline is also displayed on the dashboard; to display your event there, update src/components/Timeline/Timeline.js in the dashboard repo.