Every morning, the people who live on South Boston’s Telegraph Hill scurry out of their homes by dawn to move their cars from their free overnight spots at the South Boston Education Complex. The tow trucks, they know, will be circling shortly after 6 a.m. But this week, one SUV held its ground two mornings in a row. The car stayed put through the school day Thursday. It belongs to US Representative Stephen F. Lynch, who lives nearby in the neighborhood that’s notorious for its paucity of parking.