Retrieve participations in bulk with GET /responses/bulk

We added GET /responses/bulk, which returns participations with all their details (answers, verbatim, end customer, context, conversation...) in a single paginated call, instead of one call per participation.

It accepts the same filters as GET /responses, and is also available on /places/{id}/responses/bulk, /levels/{id}/responses/bulk and /surveys/{id}/responses/bulk.

See Participation retrieval for details.