Settings are only saved upon manual closing the app

[niklasnickel]

Description
If you make changes to the settings (local path, etc.) and let the program close automatically after synchronisation, all changes are lost. If however, you abort the automatic closing and close the program manually, all changes are saved.

To Reproduce
Steps to reproduce the behavior:

1. Go to "Einstellungen".
2. Change a parameter (e.g. toggle "Einloggen bei Programmstart")
3. Activate "Nach der Synchronisation beenden" if not already active.
4. Start a synchronisation with a clock on "Download" after wich the program closes.
5. Open up the program again.
6. The settings should not have been updated.

Expected behavior
Changed to the settings are saved
a) directly (live) upon entry or
b) leaving the settings page or
c) terminating the program in whatever way.

Requirements:

• Device: MacBook Air M1 2020, 16GB, 1TB
• OS: macOS Big Sur 11.2.3
• Version v2.3.0
• (The issue also happened on older macOS devices with older operating systems)

[t-schroeder]

This should be fixed in the latest release in our fork: https://github.com/rwthmoodle/Sync-my-L2P/releases/tag/v2.5.0