Case C-218/22, Comune di Copertino: Judgment of the Court (First Chamber) of 18 January 2024 (request for a preliminary ruling from the Tribunale di Lecce — Italy) — BU v Comune di Copertino (Reference for a preliminary ruling — Social policy — Directive 2003/88/EC — Article 7 — Article 31(2) of the Charter of Fundamental Rights of the European Union — Allowance in lieu of days of leave not taken at the end of the employment relationship — National legislation prohibiting payment of that allowance in the event of the voluntary resignation of a public servant — Control of public expenditure — Organisational needs of the public employer)