Bug 10215: (follow-up) Fix the failing test

Bug 10215: (follow-up) Fix the failing test

We now handle NULL values at the database end and do not expect empty
strings.

Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
(cherry picked from commit 117061d88420231d709515f4702446e60f7de4b6)
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>
(cherry picked from commit 5d0f6f8cbb42ac85d6648f1e0d45af359604021f)

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