Fix request page

Change

Fixes the error where if a person selects a number of filters on the Requests page and applies them, and then clicks on the next page button, they get a 503 error.

What was the cause

The error was caused by the fact that the method on the pagination button that constructs the new url expected a map of parameters, while the page was passing a MultivalueMap. This caused the MultVal map to be squashed and some information to be lost, resulting in an invalid URL.

Changes

Created new buildUrl method that accepts and properly handles a MultivalueMap and made the pagination buttons use that instead.