Remove Oral exam payment

cc @freott @vseth/1100-fv/1116-vis/vorstand

The oral exams are annoying for the following reasons:

• If we make money, it is really shady. we do not want this kind of money.
• One payment unlocks all courses, dumb as multiple orals are impossible to track.
• people have to go to ovis, which is extremely annoying if noone is there.

We can get rid of oral exams altogether by doing the following:

• If a user wants access to oral exams, they get it by default (each course separately!). We can get rid of "oral" here and allow also written exams, for cases where we do not get the pdf version of the exams in the first place. Just a big fat button "get access" with a disclaimer that they will be blocked in 6 months with no transcript etc, and that they need a reason or proof that they dropped the course or otherwise.
• After they get access, at the end of their exams, they need to upload their own protocol. The protocol needs to be reviewed and accepted by LUK.
• The student gets an e-mail reminder after their oral exam to upload the protocol, 2 daily (make sure the info is fresh), 2 weekly, then one 2 months after. LUK gets a mail to review the mod queue as otherwise they don't (bruh).
• If they do not, they get completely blocked from community solutions, with an error message.
• If they forgot their protocol, they need to go to ovis and do the walk of shame (so that protocol is less annoying and embarrassing than going there).
• we can shame them by adding a negative score (e.g. -200) and a separate counter of "missed protocols".

idk what edinburgh does, probably also something smart @takanoy