Fix conflict with filtered dataset export and paginated results

[contolini]

We use frm and search_after query params to handle paginated search results. But when a user exports a subset of our complaint database, the aforementioned pagination params are sent to the API causing it to throw an error because frm mod size != 0.

Instead of reworking the API logic it's better to just purge pagination params from export URLs because they're irrelevant. The whole point of exporting is to download all the search results and not just a single page of search results.

See DATAP-33 for more info and context.

Changes

• Updates util function that generates the export link

Testing

• yarn test should pass
• yarn cypress run --browser chrome --headless --config baseUrl=http://localhost:8000/data-research/consumer-complaints/search/ should pass
• Go to https://www.consumerfinance.gov/data-research/consumer-complaints/search/?tab=List
• Scroll to bottom and click Next > to get to page 2 of results.
• Scroll up and click Export data
• Select Filtered dataset
• Click Start export
• You should be greeted by a 400 error
• Do the above steps on localhost with this branch and it should correctly start a file download instead of 400ing

Checklist

• Changes are limited to a single goal (no scope creep)
• Code can be automatically merged (no conflicts)
• Code follows the standards laid out in the front end playbook
• Passes all existing automated tests
• New functions include new tests
• New functions are documented (with a description, list of inputs, and expected output)
• Placeholder code is flagged
• Visually tested in supported browsers and devices
• Project documentation has been updated (including the "Unreleased" section of the CHANGELOG)

[flacoman91]

I tested the api endpoint without those params.

I can't test it, but logically it seems solid 👍