Events List Shows events in 12 hour time when system uses 24 hour time

### What Happened?

I added my Nextcloud calendar through elementary online accounts CalDAV. When viewing events from calendar app's sidebar, times are listed using AM/PM rather than 24 hour time. Wingpanel calendar events use correct time, and when I add events through the calendar app, it uses 24 hour time. Interestingly, events added through elementary calendar app display in 24 hour time next to the 12 hour time entries.

#### Calendar App Screenshot:


#### Wingpanel Screenshot


Issue sounds somewhat similar to #91 ?

### Steps to Reproduce

1. Set system to use 24 hour time.
2. Add Nextcloud calendar through online accounts CalDAV.
3. Sync Nextcloud calendar.
4. Launch Calendar app and select a day to view calendar events.
5. Calendar Events which are synced use 12 hour time.

### Expected Behavior

Calendar events should be displayed in calendar app using correct system setting, in this case 24 hour time rather than 12 hour time.

### OS Version

7.x (Horus)

### Software Version

Latest release (I have run all updates)

### Log Output

_No response_

### Hardware Info

_No response_