The Dolphins are signing veteran running back Sony Michel, a league source confirmed to the Miami Herald Monday, adding another player to a crowded backfield. The 27-year-old Michel, whose signing was first reported by NFL Network, reportedly had a visit with the Dolphins last week. He was the leading rusher for the Los Angeles Rams last season, recording 845 yards and four touchdowns on a 4.1 yard per carry average. Michel also caught 21 passes for 128 yards and one touchdown. An alum of American Heritage Plantation, Michel was a first-round pick of the New England Patriots in 2018. He played…