After items search result when entering a term in date due colum filter
table is not filtered.
Its is because columns from 'Issue' must be added in _SearchItems_build_where_fragment()
like it has been added in SearchItems().
Test plan :
1) Perform an item search with some results beeing checked-out
2) In colum 'Date due' enter a number that is contained is some due
dates, ie '2022'
3) Table results are filtered with items having search term in due date
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org> Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>