Bug 25791: Remove win.print()

Bug 25791: Remove win.print()

Test plan:
1) Turn on system preference SelfCheckReceiptPrompt
2) Check out item via /cgi-bin/koha/sco/sco-main.pl
3) Click "Finish"
4) Click 'Print receipt and end session'
5) Notice two print dialog boxes right on top of each other
6) Apply patch
7) Repeat steps 1 - 4
8) Should only get a single print dialog.
9) Test in FF/Chrome and make sure behavior is consistent

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