Case C-340/19: Judgment of the Court (Sixth Chamber) of 18 June 2020 (request for a preliminary ruling from the Augstākā tiesa (Senāts) — Latvia) — Valsts ieņēmumu dienests v SIA ‘Hydro Energo’ (Reference for a preliminary ruling — Common Customs Tariff — Combined Nomenclature — Tariff classification — Tariff heading 7407 — Copper bars, rods and profiles — Hot-rolled copper or copper alloy ingots in a rectangular shape)