Case C-513/18: Judgment of the Court (Second Chamber) of 30 January 2020 (request for a preliminary ruling from the Commissione tributaria provinciale di Palermo (Italy) — Autoservizi Giordano società cooperativa v Agenzia delle Dogane e dei Monopoli — Ufficio di Palermo (Reference for a preliminary ruling — Taxation of energy products and electricity — Directive 2003/96/EC — Article 7(2) and (3) — Concept of ‘commercial gas oil used as propellant’ — National legislation levying a duty on commercial gas oil used as propellant for the regular carriage of passengers but not for the occasional carriage of passengers — Principle of equal treatment)