Bug 24765: Updated on date in Claims returned starts off as 12/31/1969

Bug 24765: Updated on date in Claims returned starts off as 12/31/1969

When an item is claimed returned by staff, there is a column called Updated On - this date field column should remain blank until this claimed returned has been updated.  Currently, when an item has been claimed returned, the date in the updated column states 12/31/1969. This date only shows up in the display, it is doesn't show up in the database like this.

Test Plan:
1) Enable return claims
2) Make a claim
3) Note the 'updated on' column has the date 1969-12-31
4) Apply this patch
5) Reload the page ( you may need to clear your browser cache )
6) Note the field is now blank

Signed-off-by: Sally <sally.healey@cheshiresharedservices.gov.uk>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>