Bug 19234: Unit tests for query parameters handling helpers

Bug 19234: Unit tests for query parameters handling helpers

This patch adds unit tests for the new query parameters handling Mojo plugin.

Sponsored-by: Camden County
Sponsored-by: ByWater Solutions
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Lari Taskula <lari.taskula@jns.fi>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>