fix: | None -> Optional

To appease the test-code-cov task in the pipeline, even though it passes
locally, and even though it's recommended against
https://discuss.python.org/t/clarification-for-pep-604-is-foo-int-none-to-replace-all-use-of-foo-optional-int/26945/6

trestlebot/tasks/sync_cac_catalog_task.py

@@ -7,7 +7,7 @@
 import os
 import pathlib
 import re
-from typing import List
+from typing import List, Optional
 
 import ssg
 from ssg.controls import ControlsManager, Policy
@@ -25,8 +25,8 @@
 
 def get_oscal_control_title(
         cac_control_id: str,
-        cac_control_title: str | None,
-        parent_title: str | None
+        cac_control_title: Optional[str],
+        parent_title: Optional[str]
 ):
     if not cac_control_title:
         return cac_control_id
@@ -47,7 +47,7 @@ def control_cac_to_oscal(
         cac_control: ssg.controls.Control,
         group_id: str,
         oscal_path: List[str],
-        parent: Control | Group | None = None
+        parent: Optional[Control | Group] = None
 ) -> Control:
     # 1. Create control and populate basics
     oscal_control = generate_sample_model(Control)