Wrong timezones for time_spans.start_user_time

**Describe the bug** time_spans.start_user_time and end_user_time are saved with the wrong timezone information (+00:00) rather than my current one (+02:00). The hour and minute are correct; the wrong timezone information make the two start time represent different instants in time (2h diff in my case). **To Reproduce** Steps to reproduce the behavior: 1. Create a time span 2. Check the records created in the SQLite database **Expected behavior** The right timezone should be saved instead of +00:00. If I create a time span at 12:30:00+00:00, start_user_time should be 14:30:00+02:00.