Option to force students to set their profile picture after sign-in

[AdamFipke]

Description

For setting the reminder, it could be implemented as simple as adding a check on the main course page that if the user does not have a profile pic URL and the courseSettings require it, then show the modal.

This gives the option for courses to get more students to set their profile picture (e.g. for in-person labs).

Success Criterias

• Add a new courseFeature/courseSetting that allows professors to keep annoyingly prompting the student to set their profile picture with a link that takes them to their profile page (e.g. pfpReminder, with default to false since this is not needed in more hybrid/online courses)
• A "skip for now" button that just hides the popup (sets modal visibility to false). Could also maybe add a "don't remind me"
• As a QoL feature, make it so that once the user updates their profile picture, to bring them back to the course page (easiest way to do this is to probably add it as a search param in the URL e.g. /profile?returncourse=2 which could then be parsed on the profile page and then displayed as a link to go back to /course/2)

The modal prompt text could be like: "Hey there! The professor of this course strongly suggests its students to have a profile picture. You can do so by clicking the link here. Note that only the professor can see your image. [skip for now] [remind me never - shows up after 5 secs] [set picture now]"