Bug description

When the user is downloading the project from the cloud on an unstable connection, the sync dialog could freeze. The dialog cannot be closed via [x] or the "Cancel" button, and the time and progress are not changing.

Steps to reproduce

1. Start cloud project downloading
2. Wait
3. Imitate network connection issues, i.e. try to toggle a VPN on and off a few times
4. Observe that Remaining time stalled or started to increase, otherwise goto 3
5. Press Cancel

Expected behavior

• The project is either downloaded or error message is shown.
• The Cancel button should work in all cases

Actual behavior

Dialog is frozen, Audacity cannot be closed

Audacity Version

Audacity 3.7.x

Operating system

macOS

Additional context

No response