Revert the fix for notification on folder deletion because it requires a big redesign. The simple fix doesn't work

src/Microsoft.DotNet.Watcher.Core/Internal/ProjectWatcher.cs

@@ -107,10 +107,6 @@ namespace Microsoft.DotNet.Watcher.Core.Internal
                 foreach (var file in project.Files)
                 {
                     closure.Add(file);
-
-                    // We need to add the folder because folder deletions only trigger 
-                    // for the folder, not for the files inside it
-                    closure.Add(Path.GetDirectoryName(file));
                 }
 
                 foreach (var dependency in project.ProjectDependencies)