Aggregates a list of result tuples into a single result tuple.

A result tuple is a two-element tuple where the first element is :ok, or :error, while the second element is the resulting data.

This function goes through a list of such tuples and aggregates the list into a single tuple where

• if all tuples in the list are :ok tuples, returns {:ok, results}

• if any tuple is an :error tuple, returns {:error, {results, errors}}

• results and errors are lists of second tuple elements in their respective tuples