Updating development with recent changes on release/9.4.x (dnnsoftwar…

…e#2964)

* Fix error running unit tests (dnnsoftware#2940)

When running tests, the following error occurs:
	VSTest: Could not locate executable.

cake-build/cake#1522 (comment)
indicates that there's an issue using VS 2019, and presents a workaround
to find the correct path

* DNN-31366 - Deleted page can still be selected as parent page (dnnsoftware#2925)

* DNN-31366 - TabController HasChildren returns false if all children are deleted

* Simplify HasChildren condition

* deleting_themes_from_Extensions_doesnt_remove_it_from_themes (dnnsoftware#2950)

* Returns the working types if some fail (dnnsoftware#2953)

DNN Platform/Library/Common/Utilities/FileSystemUtils.cs

@@ -454,7 +454,7 @@ public static void DeleteFilesRecursive(string strRoot, string filter)
                             DeleteFilesRecursive(strFolder, filter);
                         }
                     }
-                    foreach (string strFile in Directory.EnumerateFilePaths(strRoot).Where(f => f.Contains(filter)))
+                    foreach (string strFile in Directory.EnumerateFilePaths(new DirectoryInfo(strRoot)).Where(f => f.Contains(filter)))
                     {
                         try
                         {