A former White House press secretary for Donald Trump delivered a stinging rebuke to her former boss at the Democratic National Convention on Tuesday. Stephanie Grisham told Democrats on Tuesday night she wasn’t just a Trump supporter, she was a “true believer” and one of his closest advisers, spending Easter, Christmas and Thanksgiving with the Trump family at Mar-a-Lago. “Behind closed doors, Trump mocks his supporters,” she said. “He calls them basement-dwellers.” Want more breaking political news? Click for the latest headlines at Raw Story. During a pandemic-era hospital visit, as people …