By Oleksandr Kozhukhar and Pavel Polityuk LVIV/KYIV (Reuters) -Ukraine said a Russian missile attack killed seven people in Lviv on Monday, the first civilian victims in the western city, and the commander of Ukrainian forces holding out in the devastated port city of Mariupol appealed to the pope for help. Maksym Kozytskyy, the governor of Lviv which lies 60 km (40 miles) from the Polish border, said preliminary reports suggested there were four strikes, three on warehouses that were not in use by the military and another on a car service station. “It was a barbaric strike at a service statio…