Bug 495404

SUMMARY
kscreenlocker sometimes will not allow log in, only doing nothing when pressing enter after inputting the correct password.

STEPS TO REPRODUCE
1. Lock screen
2. Attempt to login with random chance of it failing

OBSERVED RESULT
kscreenlocker does nothing, input field isn't cleared, no error message appears
journalctl shows the following:

```
Oct 26 20:18:43 arch kscreenlocker_greet[31174]: file:///usr/share/plasma/shells/org.kde.plasma.desktop/contents/lockscreen/LockScreenUi.qml:128: TypeError: Property 'startAuthenticating' of object TypeError: Type error is not a function
Oct 26 20:18:47 arch kscreenlocker_greet[31174]: file:///usr/share/plasma/shells/org.kde.plasma.desktop/contents/lockscreen/LockScreenUi.qml:280: TypeError: Property 'respond' of object 1,0,0,0,0,1,0,0,0,0,1,0,0,0,0,1 is not a function
Oct 26 20:18:51 arch kscreenlocker_greet[31174]: file:///usr/share/plasma/shells/org.kde.plasma.desktop/contents/lockscreen/LockScreenUi.qml:280: TypeError: Property 'respond' of object 1,0,0,0,0,1,0,0,0,0,1,0,0,0,0,1 is not a function
```

EXPECTED RESULT
kscreenlocker should proceed with logging in 

SOFTWARE/OS VERSIONS
Operating System: Arch Linux 
KDE Plasma Version: 6.2.2
KDE Frameworks Version: 6.7.0
Qt Version: 6.8.0
Kernel Version: 6.11.5-2-cachyos-bore (64-bit)
Graphics Platform: Wayland

ADDITIONAL INFORMATION
A post regarding this issue has also been reported on discuss: https://discuss.kde.org/t/kscreenlocker-password-not-accepted-and-weird-state-trying-to-unlock/24058