Description In BigBlueButton before 2.2.29, a user can vote more than once in a single poll. References https://github.com/bigbluebutton/bigbluebutton/compare/v2.2.28...v2.2.29 https://github.com/bigbluebutton/bigbluebutton/commit/d2cb02b3bd670265c6b1ba003f87fc261e0ac3e1