removes dubplicate mc_options as atribute of problem in database.py

zesje/database.py

@@ -99,7 +99,6 @@ class Problem(db.Model):
     exam_id = Column(Integer, ForeignKey('exam.id'), nullable=False)
     feedback_options = db.relationship('FeedbackOption', backref='problem', order_by='FeedbackOption.id', lazy=True)
     solutions = db.relationship('Solution', backref='problem', lazy=True)
-    mc_options = db.relationship('MultipleChoiceOption', backref='problem', lazy=True)
     widget = db.relationship('ProblemWidget', backref='problem', uselist=False, lazy=True)
 
     @hybrid_property