Function restore_from_history_for_page_id 

pub async fn restore_from_history_for_page_id(
    conn: &mut PgConnection,
    page_id: Uuid,
    history_id: Uuid,
    authorized_source_page_id: Option<Uuid>,
    expected_course_id: Option<Uuid>,
    expected_exam_id: Option<Uuid>,
    author: Uuid,
    spec_fetcher: impl SpecFetcher,
    fetch_service_info: impl Fn(Url) -> BoxFuture<'static, ModelResult<ExerciseServiceInfoApi>>,
) -> ModelResult<Uuid>