Function headless_lms_models::library::grading::create_fixed_grading_for_submission_task

async fn create_fixed_grading_for_submission_task(
    conn: &mut PgConnection,
    submission: &ExerciseTaskSubmission,
    exercise: &Exercise,
    user_exercise_slide_state_id: Uuid,
    fixed_result: &ExerciseTaskGradingResult
) -> ModelResult<StudentExerciseTaskSubmissionResult>