Christian McCaffrey, Olivia Culpo. Frazer Harrison/Getty Images Olivia Culpo and San Francisco 49ers star Christian McCaffrey have officially tied the knot after more than four years of dating. Culpo, 32, and McCaffrey, 28, tied the knot on Saturday, June 29, in a church in Watch Hill, Rhode Island, according to Vogue. “It’s a covenant. It’s…