Team Calendar email notifications are sent one day off for positive UTC offsets

Summary

Email notifications sent to watchers have its date set to one day off of the actual event date. It happens when the calendar has its timezone set to any positive UTC offset (starting at UTC+00:00) and only for "All day" events.

Tested on:

• Confluence 1000.1692.0
• Confluence 1000.0.0-16065ca
• Team Calendar 1000.0.37
• System time set to Americas/Sao Paulo

Steps to reproduce:

1. Create a new calendar
2. Choose any positive UTC offset (can be anything ranging from UTC+00:00 to UTC+12:00)
3. Add a few watchers
4. Create an All day event

In Team Calendar's UI

Email Notification

Workaround

Do not mark events as "All Day", and instead fill out the time period.