Talking about luck I don't know if PSG can be lucky enough to beat Inter Milan in the UEFA Champions League final, but if it's 3 or more goals, it's likely to happen because both teams are two scoring sides, and they can possibly play BTTS, which can lead to over 2.5 goals. Inter Milan is a club that always gives their opponents' point man a close marking so that he will not be a threat to them, so since Dembele is a point man for PSG, I am not sure if he will have the chance to score a goal tomorrow.
The Champions League final will not be decided based on luck but by how well the team played and able to handle their opportunities. It will also be influenced by factors such as mental preparedness of the club which goes beyond skills of the players at the pitch but ability to withstand pressures, remain focus after conceding or leading in goals and many other things. My happiness is that the two teams that are playing the finals are good and can give us beautiful football so whoever wins deserve to lift the trophy.