The hearts of celebrities might be in the right place, but sometimes even the most well-intentioned social media messages land with a thud.Just ask Gal Gadot, who in March posted a video of her and her celeb pals singing John Lennon’s Imagine from their luxe homes as the rest of the world was gripped by the coronavirus crisis and mounting job losses.This week a host of white celebrities, including Julianne Moore, Sarah Paulson, Aaron Paul, Kristen Bell, Kesha, Justin Theroux, Debra Messing, Bryce Dallas Howard, Piper Perabo and others, participated in a PSA in which they “take responsibility” for racism.The two-minute black-and-white video posted to Twitter features the stars looking into the camera and saying “I take responsibility”