Bug 8338: (QA follow-up) Clean up warning

Bug 8338: (QA follow-up) Clean up warning

This patch moves the accountline->store call below the FinesLog code
such that we return the same 'thing' from _FixOverduesOnReturn as the
other clauses of the routine.

We also take the oportunity to clean up the warning thrown by an errant
call to the routine such that we output the actual itemnumber rather
than a HASH reference marker.

Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>