Ensure some results have been loaded in playlist results screen tests

Basically, the failing delayed test would fire two web requests during
the proceedings. In unfortunate timing, the first would succeed and the
test would think "everything is okay", but the actual request loading
results has not yet run.

This check ensures *something* is loaded, which seems to be enough to
make things reliable.

osu.Game.Tests/Visual/Playlists/TestScenePlaylistsResultsScreen.cs

@@ -173,6 +173,8 @@ namespace osu.Game.Tests.Visual.Playlists
         {
             AddUntilStep("wait for scores loaded", () =>
                 requestComplete
+                // request handler may need to fire more than once to get scores.
+                && totalCount > 0
                 && resultsScreen.ScorePanelList.GetScorePanels().Count() == totalCount
                 && resultsScreen.ScorePanelList.AllPanelsVisible);
             AddWaitStep("wait for display", 5);