Bug 31246: <span> displayed in 'Additional fields' section

Bug 31246: <span> displayed in 'Additional fields' section

This patch avoids escaping HMTL data in the additional fields section.

To test:
1. Open the additional fields section
   http://kohadev-intra.mydnsname.org:8081/cgi-bin/koha/admin/additional-fields.pl
=> FAIL: there are some nasty <span> </span> texts in there
2. Apply this patch
3. Reload
=> SUCCESS: Things display nicely again!
4. Sign off :-D

Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
Signed-off-by: Emmanuel Bétemps <e.betemps@gmail.com>
Signed-off-by: Victor Grousset/tuxayo <victor@tuxayo.net>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
(cherry picked from commit a7272f988679904d3f018550a73719fc102b3425)

Signed-off-by: Lucas Gass <lucas@bywatersolutions.com>