fix(explore): make sure sort by metric is not duplicated (#13473)
fix(explore): make sure sort by metric is not duplicated (#13473)


airbnb/caravel,zhouyao1994/incubator-superset,airbnb/caravel,mistercrunch/panoramix,apache/incubator-superset,apache/incubator-superset,zhouyao1994/incubator-superset,mistercrunch/panoramix,zhouyao1994/incubator-superset,apache/incubator-superset,zhouyao1994/incubator-superset,apache/incubator-superset,mistercrunch/panoramix,airbnb/caravel,apache/incubator-superset,zhouyao1994/incubator-superset,airbnb/caravel,mistercrunch/panoramix