Add CSV export functionality to RA Management search results

As an institution administrator, I want to obtain a CSV export of my RA, RAA, Either users, so that I can more easily perform periodic audits.

SD-127644 and SD-127154 for more details on user motivation.

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The Tokens page already offers a CSV export of search results:

The RA Management page already offers search and filter functionality for looking up RA, RAA, and users with either role.

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This feature request expands the functionality in the RA Management page to include an Export button.

• Add an Export button next to the Search button on the RA Management page. This button should export the search results in CSV format.
• The naming convention for the exported file should follow the convention from the Tokens page. So, something like ra_export_YYYY-MM-DD, raa_export_YYYY-MM-DD, ra-raa-export_YYYY-MM-DD.
• In the Role dropdown, there are currently three options: Blank, RA, and RAA. It would be good to name the Blank option with a more descriptive name. So the options list may look something like RA/RAA, RA, RAA.
• All other scope boundaries behave as normally. In other words, an administrator may only search for and export the RA(A) overview for the institution for which they are responsible.