Bulkrax exporter page timing out

[cziaarm]

Story

Bulkrax 5.3.1 stalls when export pages have more than a few hundred exports.

Acceptance Criteria

Export page for kew (321 exports) failing to load in time (504). This page should load... either negotiating down the number of exports, but preferably by better pagination (Bulkrax >= 7)

pull/582

Testing Instructions and Sample Files

Go to https://kew.iro.bl.uk/exporters?locale=en

Don't get a timeout message?