[REF] [EXPORT] partial cleanup on adding fields to returnProperties based on usage

[eileenmcnaughton]

Overview

Minor code cleanup in export - partial of #14782

Before

Less readable

After

More readable

Technical Details

In general we are moving to wrangling information in less places - with the construct generally setting the various properties we need to work with

Comments

[civibot]

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[eileenmcnaughton]

@colemanw well this small one is passing now.