Run CleanUp on TaskPool

csharp/App/Backend/Database/Db.cs

@@ -1,3 +1,4 @@
+using System.Reactive.Concurrency;
 using System.Reactive.Linq;
 using InnovEnergy.App.Backend.DataTypes;
 using InnovEnergy.App.Backend.DataTypes.Methods;
@@ -39,8 +40,9 @@ public static partial class Db
 
         Observable.Interval(TimeSpan.FromDays(0.5))
                   .StartWith(0)         // Do it right away (on startup)      
+                  .ObserveOn(TaskPoolScheduler.Default)
                   .SelectMany(Cleanup)
-                  .Subscribe();         // and then daily
+                  .Subscribe();
     }