[Bug] Can't change UI language via settings

**Describe the bug**
Can't change UI language via settings

**To Reproduce**
Steps to reproduce the behavior:
1. Go to settings
2. Change language from current language (German) to another language (English in my case)
3. Click apply
4. Restart CopyQ

**Expected behavior**
Steps should change the language, but the UI language stays German even after restart of app.

**Screenshots**
If applicable, add screenshots to help explain your problem.

**Version, OS and Environment**
- Application Version: Latest (3.13.0)
- OS: Windows 8.1

**Additional context**
This is a fresh installation of CopyQ - no other settings were made. For any other language but English a popup is shown stating that I need to restart the application to apply the language change. But the lanuage stays German regardless of which one I pick.