Summary

While setting the start & end date of a sprint, the datetime picker UI still shows in 12hrs format (AM/PM). Even though the date format has been changed to 24hrs in Jira settings.

Steps to Reproduce

1. Click on Settings > System > General Configuration, select Advanced Settings
2. Change the date Time range picker format to 24h format using this documentation:
   • https://confluence.atlassian.com/jira063/how-to-change-the-date-time-range-picker-format-to-24h-format-683542334.html
3. Go to Scrum board and create sprint and add any issue to the sprint
4. Click the start sprint option and when setting the dates and times for it to start/end, press the calendar icon.

Expected Results

The pop up calendar shows the time in 24h when selecting the date and times.

Actual Results

The time is still shown in 12h format. It is "translated" correctly to 24h in the resulting date, but the UI of the date picker itself still shows AM/PM.

 h3. Notes
The issue only exist when changing the start/end date of a sprint. Everywhere else does not show a similar issue.