Check pagination is DB not in-memory for Admin API

[s1monj]

While we're on the subject of pagination

• Listing observations and patients from the web console (Admin API) could be large and needs to use pagination
• Verify that the default pagination system for the Admin API endpoints uses DB limit/offset and not in-memory pagination
• If it does not use DB pagination update the default paginators for all Admin API endpoints (except for Organizations that uses a custom response) accordingly