Bug 26908: Restore ability to view and select EDI plugins for a vendor account

Bug 26908: Restore ability to view and select EDI plugins for a vendor account

Test Plan:
1) Install an EDI plugin
2) Browse to edi_accounts.pl, create or edit an account
3) Note the plugins pulldown is missing
4) Apply this patch
5) Restart all the things!
6) Reload the page
7) Note the pulldown is back!

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
(cherry picked from commit 0d438de0186fb08d2a1f8eb82b0df0204efff5ef)

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