legacy: fix import in bibstat cli
legacy: fix import in bibstat cli

* Fixes import in bibstat script.  (closes #2293)

Signed-off-by: Jiri Kuncar <2bdffcb416fed3002465740d19a053a39918cbe5@cern.ch>

tiborsimko/invenio,inveniosoftware/invenio,inveniosoftware/invenio,tiborsimko/invenio