get https://api.ottolearn.io/v1/rest/Leaderboard.GetLeaderboardUserSummaries
List all Leaderboards User Summaries in an organization. Provides number of ranked Users (Number of Users got ranked by participating in leaderboard contest) for each leaderboard in an organization. For Leaderboards which group their results by attribute (Example: Department), it will also display ranked Groups (Number of Groups got ranked by groups' users participating in leaderboard contest)