Amazon.com Inc.’s Ring home doorbell unit says it will stop letting police departments request footage from users’ video doorbells and surveillance cameras, retreating from a practice that was criticized by civil liberties groups and some elected officials.Next week, the company will disable its Request For Assistance tool, the program that had allowed law enforcement to seek footage from users on a voluntary basis, Eric Kuhn, who runs Ring’s Neighbors app, said in a blog post on Wednesday. Poli...