[REF] Fix handling of owner url parameter from Membership Dashboard

[seamuslee001]

Overview

This picks up a comment from @jitendrapurohit #16933 (comment) that the owner url parameter wasn't correctly being passed on for export and related purposes

Before

Owner URL param not respected in membership search export

After

Owner URL param respected

Technical Details

The member_is_primary field has not been added to the entity information yet and this is consistant with some other changes we have done for other url parameters e.g. https://github.com/civicrm/civicrm-core/blob/master/CRM/Contribute/Form/Search.php#L126

ping @jitendrapurohit @eileenmcnaughton

[civibot]

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[eileenmcnaughton]

I'm fine with this approach - happy to be conservative here & do a narrow fix

[eileenmcnaughton]

Screen shot from demo site looks good