run postfetch_post_update for version_id_col even if delete

run postfetch_post_update for version_id_col even if delete

Fixed issue where using :meth:`_orm.Session.delete` along with the
:paramref:`_orm.Mapper.version_id_col` feature would fail to use the
correct version identifier in the case that an additional UPDATE were
emitted against the target object as a result of the use of
:paramref:`_orm.relationship.post_update` on the object.  The issue is
similar to :ticket:`10800` just fixed in version 2.0.25 for the case of
updates alone.

Fixes: #10967
Change-Id: I959e9a2cc3e750e86e8de7b12b28ee1e819ed6d8