[dataimport] Fix method signature
Since d4bd28d5fca8, _storage_handler expect 4 args.
grafted from b089858c49a2806b6ea8a7ee66773436701e947c (3.22)
related to #9177565.
# -*- coding: utf-8 -*-
# copyright %(year)s %(author)s, all rights reserved.
# contact %(author-web-site)s -- mailto:%(author-email)s
#
%(long-license)s
"""%(distname)s precreate script, executed at instance creation time or when
the cube is added to an existing instance, before the schema is serialized.
This is typically to create groups referenced by the cube'schema.
"""