Temporarily revert "version up : Zope 2.12.23." in erp5 branch whose change on...
Kazuhiko Shiozaki authored
Temporarily revert "version up : Zope 2.12.23." in erp5 branch whose change on ObjectManager's behaviour breaks some ERP5 tests, that should be fixed in ERP5 side anyway.

This reverts commit 529d7892.
6ab7c31f