adds seed scripts which generate more realistic data

[Snorre98]

Still draft! Will fix formating/linting

This changes some of the seed scripts related to recruitments so that they generate more realistic data.
❗ Adding more realistic seed data has revealed that we need to implement pagination on some pages, like the user admin page. We will also have to filter more data in the backend, like the data being fetched on recruitment position overview page for gangs.

• The user seed script is changed to generate 1500 users.
• The application seed script is changed to create 1200 new applicant users in addition to generating applications
  • "applicant user" cannot be represented in the database. In real cases this is wanted, but in seed data it is hard to differentiate between applicants and interviewers
• The interviewer seed script has been optimized, and there is differentiation between applicants and interviwers
• The positions seed script has been changed to make more realistic data, as well as rectricting the creation of positions for gangs which does not exsist in some organization
  - Before it was possible for the seed script to generate positions for gangs not available through the UI (like Organizational Resources at Samfundet)
• The occupied time slot seed script has been updated to be more realistic, with more random but strucutred occupied times.
  • ❗ It is very slow (around 50 sec on my machine, generates 750 000++ occupied timeslots)
  • It only creates occupied timslots for users which are interviewers or applicants