Bug 11175: (follow-up) make atomic update idempotent
Atomic update tries to insert line into system preferences even if it's
already there. This patch fixes that by adding 'IGNORE' to the query,
making it idempotent.
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com> Signed-off-by: Andrew Nugged <nugged@gmail.com> Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl> Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>