Joined Cases C-58/20 and C-59/20: Judgment of the Court (First Chamber) of 17 June 2021 (request for a preliminary ruling from the Bundesfinanzgericht — Austria) — K (C-58/20), DBKAG (C-59/20) v Finanzamt Österreich, formerly Finanzamt Linz (References for a preliminary ruling — Value added tax (VAT) — Directive 2006/112/EC — Article 135(1) — Exemptions — Management of special investment funds — Outsourcing — Services provided by a third party)