Bug 18806: Fix batch revert

Bug 18806: Fix batch revert

Since bug 18242: When a biblio is deleted, a new transaction is created.
tools/manage-marc-import.pl use the AutoCommit flag, which does not
allow nested transaction.
AutoCommit must not be used.

Test plan:
Import a batch, then revert it.
The biblios must have been correctly deleted, they were not before this
patch

Signed-off-by: Lee Jamison <ldjamison@marywood.edu>
Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>