Case T-546/20: Judgment of the General Court of 1 December 2021 — Sopra Steria Benelux and Unisys Belgium v Commission (Public service contract — Tender procedure — Services for the specification, development, maintenance and support of IT platforms for DG ‘Taxation and Customs Union’ — Rejection of tender submitted by a tenderer and award of the contract to another tenderer — Obligation to state reasons — Abnormally low offer)