Daniel Radcliffe and his longtime girlfriend, Erin Darke, have welcomed their first baby.   The couple were spotted pushing a stroller on a walk in New York City Monday, April 24, in photos obtained by the Daily Mail.   Harry can be seen wearing a protective face mask and baseball cap while pushing the stroller, which was covered with a blanket to hide their child’s face.   News broke in March that the “Miracle Workers” co-stars were starting a family.   Darke, 38, …