Registering an event with [Alt][Enter] on a Date or Time widget does not save the date or time

[Pierre DAVID]

Describe the bug
When pressing [Alt][Enter] in a date-time widget, date or time is not updated in event.

If applicable: Stack Trace
N/A

To Reproduce
Using ikhal, add an event, then modify a date (start or end) or a time (start or end) without leaving the widget, then use [Alt][Enter] to register the event.

Expected behavior
Event should include the modified date or time.

Screenshots
N/A

OS, version, khal version and how you installed it:

• The output of khal --version: khal, version 0.11.3.dev1+gb8a987a
• Installation method : git + pip
• python version python 3.11
• OS : linux x86_64

Additional context
N/A