fix files

src/SharpIDE.Godot/Features/Common/TreeItemContainer.cs

@@ -8,16 +8,3 @@ public class TreeItemContainer
 {
     public TreeItem? Value { get; set; }
 }
-
-public static class ObservableTreeExtensions
-{
-    public static ObservableHashSet<T> WithInitialPopulation<T>(this ObservableHashSet<T> hashSet, Action<ViewChangedEvent<T, TreeItemContainer>> func) where T : class
-    {
-        foreach (var existing in hashSet)
-        {
-            var viewChangedEvent = new ViewChangedEvent<T, TreeItemContainer>(NotifyCollectionChangedAction.Add, (existing, new TreeItemContainer()), (null!, null!), -1, -1, new SortOperation<T>());
-            func(viewChangedEvent);
-        }
-        return hashSet;
-    }
-}