Case C-909/19: Judgment of the Court (Tenth Chamber) of 28 October 2021 (request for a preliminary ruling from the Curtea de Apel Iaşi — Romania) — BX v Unitatea Administrativ Teritorială D. (Reference for a preliminary ruling — Protection of the safety and health of workers — Directive 2003/88/EC — Organisation of working time — Article 2(1) and (2) — Concepts of ‘working time’ and ‘rest period’ — Mandatory vocational training undertaken at the employer’s request)