FBI Director Kash Patel on Tuesday questioned why Sen. Chris Van Hollen would have “margaritas with a felon” and run up a $7,000 bar tab in Washington, DC — before daring the Maryland Democrat to take a test alongside him for alcohol dependency. “The only person that was slinging margaritas in El Salvador on the taxpayer dollar with a convicted, gang-banging rapist, was you,” Patel erupted in a Senate appropriations subcommittee hearing. Follow The Post’s live coverage of President Trump and