Refactor preloading users in REST API

lib/api/users.rb

@@ -120,9 +120,11 @@ module API
         users = reorder_users(users)
 
         entity = current_user&.admin? ? Entities::UserWithAdmin : Entities::UserBasic
-        users = users.preload(:identities, :u2f_registrations) if entity == Entities::UserWithAdmin
-        users = users.preload(:identities, :webauthn_registrations) if entity == Entities::UserWithAdmin
-        users = users.preload(:namespace) if entity == Entities::UserWithAdmin
+
+        if entity == Entities::UserWithAdmin
+          users = users.preload(:identities, :u2f_registrations, :webauthn_registrations, :namespace)
+        end
+
         users, options = with_custom_attributes(users, { with: entity, current_user: current_user })
 
         users = users.preload(:user_detail)