LOS ANGELES—John Langley, who was the creator of the long-running TV series “Cops,” has died during a road race in Mexico, a family spokeswoman said. Langley died in Baja, Mexico, of an apparent heart attack Saturday during the Coast to Coast Ensenada–San Felipe 250 off-road race, family spokeswoman Pam Golum said. He was 78. “Cops”…