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> <para>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.</para> </important>