Several updates are needed to the timezone selector on the report creation page. These updates will make the feature more useful for a larger set of Wikimetrics users.

1. Include all timezones (only 10 timezones currently available)
2. Use timezone numbers only, not labels. Current labels are Global-north centric and may be confusing (i.e. there are many people in UTC +1:00 who are not in "Central European Time")
3. reverse the order of the dropdown list so it is starts with the lowest negative number (i.e. -10:00 UTC) and extends to the highest positive number (i.e. +10:00 UTC)