HHH-1283: ScrollableResults JoinFetch don't set child collection correctly

A customer reported an issue with the ScrollableResults JoinFetch, where ScrollableResults set child collection correctly at the first parent object, but after the second parent object only the first element of a child collection was included. The ScrollableResults logic has been improved to read sequentially. When a new parent is encountered, ScrollableResults assumes it has finished processing all rows for the previous parent. IMPORTANT This fix relies on results being ordered consistently. Because some databases do not return sorted data (such as H2) you should explicitly apply "order by" for ScrollableResults result ordering.