President Biden on Friday night will host a concert by superstar Elton John on the White House lawn — providing the exclusive venue for the filming of a TV special.Biden and first lady Jill Biden will speak at the 8 p.m. concert put on by A&E Networks, which will then air the special at an undisclosed future date.“Tonight, as you all know, we will be welcoming Sir Elton John,” White House press secretary Karine Jean-Pierre said at her regular press briefing — after journalists heard mic checks from the adjacent driveway.