dedup migration

Jellyfin.Server/Migrations/MigrationRunner.cs

@@ -24,7 +24,6 @@ namespace Jellyfin.Server.Migrations
             typeof(Routines.MigrateUserDb),
             typeof(Routines.ReaddDefaultPluginRepository),
             typeof(Routines.MigrateDisplayPreferencesDb),
-            typeof(Routines.MigrateDisplayPreferencesDb),
             typeof(Routines.RemoveDownloadImagesInAdvance),
             typeof(Routines.DownloadTheTvdbPlugin)
         };