Do not attempt to add displayed score to list of sorted scores more than once

This is a very dodgy fix, but it fixes an edge case that has so far - to
my knowledge - not been reported by users in the wild, only by me trying
to break things, so my hope is that we can do this and move on for now.

osu.Game/Screens/Ranking/SoloResultsScreen.cs

@@ -74,6 +74,12 @@ namespace osu.Game.Screens.Ranking
                 // this simplifies handling later.
                 if (clonedScore.Equals(Score) || clonedScore.MatchesOnlineID(Score))
                 {
+                    // this is a precautionary guard that prevents `Score` from appearing multiple times in the list.
+                    // that can occur in rare cases wherein two local scores have the same online ID but different replay contents
+                    // (this is possible e.g. in cases of client-side vs server-side recorded replays, see https://github.com/ppy/osu-server-spectator/issues/193)
+                    if (sortedScores.Contains(Score))
+                        continue;
+
                     Score.Position = clonedScore.Position;
                     sortedScores.Add(Score);
                 }