Bug 32530: When duplicating child card, guarantor is not saved

Bug 32530: When duplicating child card, guarantor is not saved

When duplicating a child card with a guarantor, the guarantor information
appears during the card creation process, but disappears as soon as saving
the card. To recreate:

1. Find a card with a guarantor, either patron or non-patron guarantor.
2. Duplicate the card. Note that it appears to be working on the card
   creation screen.
3. Save the patron after completing the form. The guarantor is now gone.

New test plan:
1. Find a card with a guarantor, either patron or non-patron guarantor.
2. Duplicate the card. Note that it appears to be working on the card
   creation screen.
3. Save the patron after completing the form. The guarantor is now gone.
Apply patch and repeat, the guarantor should stay after 3.

Note, I may not have understood the code but it looks like nothing is
searching for the content of the displayed information. Therefore I add
hidden fields that are copies of those provided in guarantor_template
class

Signed-off-by: Emmi Takkinen <emmi.takkinen@koha-suomi.fi>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Katrin Fischer <katrin.fischer@bsz-bw.de>