Ordered delete

[hjanott]

In #3313 we introduced sorting on the fields when deleting an instance. It needs to be discussed whether this is actually needed. In case that this is only relevant for testing, it should be changed.

[vkrasnovyd]

Discussed.
Decision: keep sorting the data of db_instance by field names when generating events for cascade deletions.
Reasons:

• Easier and faster development of the future functionality because of predictable history entries order
• Minimal impact on performance