Bug 32413: Fix repeated param names for JSON report

Bug 32413: Fix repeated param names for JSON report

This patch fixes repeated param names for JSON report.

To test:

1) Create a report
    SELECT count(*) from items where homebranch = <<Branchcode>>
    UNION ALL
    SELECT count(*) from deleteditems where homebranch = <<Branchcode>>
2) Run the report as JSON, cgi-bin/koha/svc/report?id=<id>&sql_params=<Branchcode>
3) Check that the second value is 0
4) Apply the patch
5) Run the report as JSON again
6) Check that the second value has the correct value
7) prove t/db_dependent/Koha/Reports.t

Sponsored-by: Koha-Suomi Oy
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Katrin Fischer <katrin.fischer@bsz-bw.de>