Bug 14614: Multiple URLs (856) in cart/list email are broken

Bug 14614: Multiple URLs (856) in cart/list email are broken

To reproduce:
- Add multiple subfields 856 u to a bilbio
- Add this biblio to a cart and send it as mail
  (from Staff client and from OPAC)
Result: Links in mail body are broken

To test
- Apply patch
- Send carts again (from Staff client and from OPAC)
- Result: In mail body, links display separated with blank-pipe-blank
  like http://bla.com | http://blabla.com | http://blablabla.com
- Change one of the 856 u to not to be a link, e.g. äöü
- Send carts again
- Verify that in mail body äöü correctly display as text.

(Amended to make it work for OPAC as well, MV)

Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
Signed-off-by: Brendan A Gallagher <brendan@bywatersolutions.com>
(cherry picked from commit d135499d2893fe1000c627f433395989d7d9e022)
Signed-off-by: Julian Maurice <julian.maurice@biblibre.com>