Bug 31086: (QA follow-up) Improve atomicupdate to be more resilient

Bug 31086: (QA follow-up) Improve atomicupdate to be more resilient

We now populate the branchcode field with the first available branch on
the system if we find it to be NULL before we set the NOT NULL

Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
(cherry picked from commit 5fa510b431c043671c7bcb73c431c60aac0039ed)

Signed-off-by: Lucas Gass <lucas@bywatersolutions.com>
(cherry picked from commit 13a3b0be9c0ba1a2dfc33cdf8b4845fefdb372d1)
Signed-off-by: Arthur Suzuki <arthur.suzuki@biblibre.com>