Bug 16612 - Cannot set "Until date" for "Enrollment period" for Patron Categories

Bug 16612 - Cannot set "Until date" for "Enrollment period" for Patron Categories

Attempting to set an "Until date" date for "Enrollment period" will
result in the date being accepted but not saved.

Test Plan:
1) Attempt to set an enrollment period until date for a new patron category
2) Note the period is not saved
3) Apply this patch
4) Attempt to set the enrollment period date again
5) This time it should save!

Signed-off-by: Andrew Brenza <abrenza@audubonlibrary.org>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
(cherry picked from commit 2af028bb13273d2b13f6e5cf417436fc0c8764f7)
Signed-off-by: Frédéric Demians <f.demians@tamil.fr>
(cherry picked from commit 90d3635fedb18acb652134e1541827a888e1bef5)
Signed-off-by: Julian Maurice <julian.maurice@biblibre.com>