Wrong `TimeZone` on `CesiumSunSky` in various levels

[j9liu]

Levels like 01_CesiumWorld and 02_CesiumMelbourne use a time zone that is not actually accurate to the region. Then, the solar time is set very early or late to compensate.

This isn't a problem when simply opening + viewing the level, but if you ever try to reposition the georeference, it updates the timezone for that longitude. This can result in total darkness if the solar time is late at night.