Use optional for Py<3.10

Author: ReeceHumphreys

src/utilities/supportData/dataFetcher.py

@@ -21,6 +21,7 @@
 import functools
 import requests
 import pooch
+from typing import Optional
 
 from Basilisk.utilities.supportData.registrySnippet import REGISTRY
 from Basilisk import __version__
@@ -70,7 +71,7 @@ def select_base_url() -> str:
     return fallback if DATA_VERSION == "v0.0.0" or not tag_exists(tag_url) else tag_url
 
 
-def find_local_support_data() -> Path | None:
+def find_local_support_data() -> Optional[Path]:
     """
     Return the path to the local ``supportData`` directory if running
     from a cloned repo in editable mode, otherwise return ``None``.