Update QueryPagination.java code for better paginated iteration #2073

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Is your feature request related to a problem? Please describe.
With regards to the query pagination example, the existing example doesn't cover scenario to iterate through all next row page-by-page. And I couldn't find an example to do so anywhere else.

Describe the solution you'd like
An easier approach would be to iterate 1st page in the result and then loop through next pages while updating result object

Describe alternatives you've considered
I have tried using iterateAll(), but it fetches all rows at once, instead iteration should be page-by-page as defined query config pageSize.