Case C-521/18: Judgment of the Court (Fifth Chamber) of 28 October 2020 (request for a preliminary ruling from the Tribunale Amministrativo Regionale per il Lazio — Italy) — Pegaso Srl Servizi Fiduciari, Sistemi di Sicurezza Srl, YW v Poste Tutela SpA (Reference for a preliminary ruling — Procurement in the water, energy, transport and postal services sectors — Directive 2014/25/EU — Article 13 — Activities relating to the provision of postal services — Contracting entities — Public undertakings — Admissibility)