Removing "don't reset connection for each transaction" option broke translations copy

We recently stopped resetting connections after every transaction, and correspondingly removed the transaction manager's reset_after_transaction field.

Except the translations copying script still set this option in one code path (now unnecessarily), where setting this option now results in an error. Since the mock transaction manager we use to test this code was not updated to remove reset_after_transaction, the test kept passing.

This is a problem for opening the Intrepid translations, which we are aching to do.