Add deprecation for ctkDirectoryButton::Option and ctkDirectoryButton::Option enums

[jcfr]

After integrating pull request

• COMP: Update C++ source files removing code specific to Qt 4 #1127

We observed that project directly using the enum failed to build:

/path/to/Slicer-Release/Slicer-build/Modules/Scripted/DICOMLib/Widgets/ui_qSlicerDICOMExportDialog.h:185:64: error: ‘ShowDirsOnly’ is not a member of ‘ctkPathLineEdit’
  185 |         PathLineEdit_OutputFolder->setOptions(ctkPathLineEdit::ShowDirsOnly);
      |                                                                ^~~~~~~~~~~~

See Slicer/Slicer#7127 (comment)

Considering that ctkDirectoryButton and ctkPathLineEdit both derive from QWidget and user code may use references to option like ctkPathLineEdit::ShowDirsOnly (instead of QFileDialog::ShowDirsOnly), this was reverted through the integration of:

• COMP: Revert removal of custom CTK Dialog options #1128

To support existing use case, the old API should instead be deprecated.