api/add_forge_now: Allow to use requests list endpoint with datatables
datatables is the javascript library we use on the frontend side to display interactive tables.
As we use server-side processing, table data must be provided in a paginated way by an HTTP endpoint.
Response format expected by datatables is different from the one returned by the Web API endpoint listing add-forge requests.
So adapt the response format of that endpoint when we know the input request has been sent by datatables.
Related to T3989 Related to T3991
Migrated from D7344 (view on Phabricator)