gpui: Return `None` for non-existing credentials in `read_credentials` on windows (#43540)

Release Notes:

- N/A *or* Added/Fixed/Improved ...
b9af6645e3Lukas Wirth committed on 11/26/2025, 12:01:01 PM· committed by GitHubparentc2cb76b
1 file changedLine totals unavailable