Add Past Enrollment Popup

[Douglas-Hong]

Summary

• Now that the enrollment history endpoint is implemented, we can bring back and improve the Past Enrollment popup.
• Currently, the popup just displays the enrollment history of the most recent lecture section offered.

Demo:

enrollmentDemo.mp4

TODO

• Make a request to PeterPortal to get the enrollment history, and parse the response
• Create the popup and display an enrollment history graph
• Cache responses
• Add ZotTracker link

Test Plan

• Verify this works for classes in the most recent quarter (e.g. CS 132).
• Verify this works for classes that haven't been offered very recently (e.g. CS 122D from Spring 2023).
• Verify this works for classes that have never been offered before (force queryEnrollmentHistory to return null).
• Make sure it looks good on dark and light mode, as well as mobile.

Issues

Closes #341
Closes #182

Future Followup

• We should allow the user to see the enrollment history of any lecture that was previously offered: Allow past enrollment popup to show the enrollment history of all previous quarters #830

[KevinWu098]

That's seriously hot 💯

[MinhxNguyen7]

Great feature, looks great. Only have a few readability suggestions.

[ap0nia]

Looks great 🚀

Most of the improvements are regarding JS syntax. The comments regarding lower level implementation details can be applied at your discretion.

[ap0nia]

Good work 🚀

All the comments I left were personal opinions. Feel free to peruse them before merging!

Addressed changes, and approved by Brian