Origin/#25 get subject from database

Fix logic for enrolling student to course. Botgh creating and enrolling student to course now implemented

backend/crud.py

@@ -20,11 +20,12 @@ def create_student(db: Session, student_email: str):
 
 def enroll_student_to_course(db: Session, course_id: str, student_email: str):
     db_course = get_course(db, course_id=course_id)
-    db_student = get_student(db, student_email = student_email)
+    db_student: schemas.Student = get_student(db, student_email = student_email)
     db_course.students.append(db_student)
     db.commit()
     db.refresh(db_course)
     db.refresh(db_student)
+    print("enrolling student to course")
     return db_student