Bug 35441: Fix typo 'UniqueItemsFields' system preference

Bug 35441: Fix typo 'UniqueItemsFields' system preference

Typo in message :
NOTE: Fields listed in the 'UniqueItemsFields' system preference will not be copied

The preference is Item without 's' : 'UniqueItemFields'

Test plan :
1) Check system preference 'UniqueItemFields' contains values
2) Go to acquisition to create a new order from new record
3) Check the note you see with the system preference

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Lucas Gass <lucas@bywatersolutions.com>
Signed-off-by: Katrin Fischer <katrin.fischer@bsz-bw.de>
(cherry picked from commit 08cc74a9b60d85fcdf5b3febfa5653111a16d9ac)
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>
(cherry picked from commit 0aea3a0f42f79768725933c2b552334a4dc8ef09)
Signed-off-by: Lucas Gass <lucas@bywatersolutions.com>