Fix room apportionment method in go_brr

[tzussman]

Change how we distribute students across rooms in go_brr so that we can get rid of the if student_index < student_count: line. Allocate students per room so that the total number of seats we allocate equals the number of students instead of more than it. Will require doing something slightly more sophisticated than the current num_seats = math.ceil(student_count / seat_count * int(rcount))