fix: support Directory.GetFileSystemEntries with enumeration options (

#966)

Implement the missing wrapper method `Directory.GetFileSystemEntries(string, string, EnumerationOptions)`.

src/TestableIO.System.IO.Abstractions.Wrappers/DirectoryWrapper.cs

@@ -162,7 +162,7 @@ public override string[] GetFileSystemEntries(string path, string searchPattern,
         /// <inheritdoc />
         public override string[] GetFileSystemEntries(string path, string searchPattern, EnumerationOptions enumerationOptions)
         {
-            throw new NotImplementedException();
+            return Directory.GetFileSystemEntries(path, searchPattern, enumerationOptions);
         }
 #endif