KOPAVOGUR, Iceland — Antonio Barretta had just realised a childhood dream. The delivery driver from San Marino, playing for the country’s league champion, Tre Penne, had scored in the Champions League under leaden skies, in an Icelandic downpour, in front of 621 supporters. But his moment was missing something. “It’s a little bit disappointing because there was no Champions League music before the game, you know? ‘The Champions!’” Barretta told…