Crash when editing reminder event

[Futsch1]

Describe the bug The app will crash if a large number is entered for the time field in the edit reminder screen.

To Reproduce Steps to reproduce the behavior:

1. Enter the edit reminder screen for an arbitrary reminder event
2. Start editing the time, but dismiss the time picker.
3. Enter the time edit field and use the keyboard to enter 100
4. Close the screen

Expected behavior It should not be possible to enter an invalid number