ContextWindow: Context has not to be Disposed

https://stackoverflow.com/questions/15666824/entity-framework-and-calling-context-dispose

https://blog.jongallant.com/2012/10/do-i-have-to-call-dispose-on-dbcontext/

Elwig/Windows/ContextWindow.cs

@@ -39,18 +39,11 @@ namespace Elwig.Windows {
             await OnRenewContext();
         }
 
-        protected override void OnClosed(EventArgs evt) {
-            base.OnClosed(evt);
-            Context.Dispose();
-        }
-
         protected async Task RenewContext() {
             if (!_renewPending) return;
-            var old = Context;
             Context = new();
             await OnRenewContext();
             _renewPending = false;
-            old.Dispose();
         }
 
         abstract protected Task OnRenewContext();