Bug 24138: Move the calculation out of the sub

Bug 24138: Move the calculation out of the sub

No changes expected here. For the next patch we are going to need to add
test and calculate the new debarment date. To ease the writing of these
tests the calculation is moved out of the existing subroutine.

Signed-off-by: Hugo Agud <hagud@orex.es>
Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Joy Nelson <joy@bywatersolutions.com>
(cherry picked from commit 1bf0904d2817c250ec7ef70667c7631e4f24d12f)

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