Fix <PrevNextButtons> index when using paginated results

[slax57]

Problem

Fix #10136

Solution

Fix the index computation in case the data comes from the query cache and page > 1

How To Test

The fix can be tested in Storybook or in the E-commerce Demo

Additional Checks

• The PR targets master for a bugfix, or next for a feature
• The PR includes unit tests (if not possible, describe why)
• The PR includes one or several stories (if not possible, describe why)
• The documentation is up to date -> no need

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