Joined Cases C-52/21 and C-53/21: Judgment of the Court (Seventh Chamber) of 24 February 2022 (requests for a preliminary ruling from the Cour d’appel de Liège — Belgium) — Pharmacie populaire — La Sauvegarde SCRL v État belge (C-52/21), Pharma Santé — Réseau Solidaris SCRL v État belge (C-53/21) (References for a preliminary ruling — Freedom to provide services — Article 56 TFEU — Restrictions — Tax legislation — Corporation tax — Obligation for purchasers of services to draw up and submit supporting documents to the tax authorities concerning amounts invoiced by suppliers of services established in another Member State — No such obligation regarding purely domestic supplies of services — Justification — Effectiveness of fiscal supervision — Proportionality)