Fix distinction between errors and exercises within MarkdownRenderer
Fix distinction between errors and exercises within MarkdownRenderer

RealSilo/twist,RealSilo/twist,yannvery/twist,doug-c/mttwist,radar/twist,radar/twist,yannvery/twist,RealSilo/twist,doug-c/mttwist,yannvery/twist,doug-c/mttwist,radar/twist