My Pillow CEO Mike Lindell, a die-hard supporter of former President Donald Trump who offered a $5 million reward to any cybersecurity expert who disproved his conspiracy theory about the 2020 U.S. presidential election, was ordered Wednesday by an arbitration panel to pay up after a Trump voter called his bluff. Robert Zeidman, a 63-year-old software developer from Nevada, sued Lindell for breach…