Use dataset to fetch record after insert

Similarily to what Update command do, use `dataset` to load the tuple
after `insert` in Create command. This way it loads "raw" data, without
applying read types yet. So when tuples are passed into `finalize` hook,
it can properly apply these read types.

lib/rom/sql/commands/create.rb

@@ -46,15 +46,15 @@ def finalize(tuples, *)
         # @api private
         def insert(tuples)
           pks = tuples.map { |tuple| relation.insert(tuple) }
-          relation.where(relation.primary_key => pks).to_a
+          relation.dataset.where(relation.primary_key => pks).to_a
         end
 
         # Executes multi_insert statement and returns inserted tuples
         #
         # @api private
         def multi_insert(tuples)
           pks = relation.multi_insert(tuples, return: :primary_key)
-          relation.where(relation.primary_key => pks).to_a
+          relation.dataset.where(relation.primary_key => pks).to_a
         end
 
         # Yields tuples for insertion or return an enumerator