LIMS-2081: Remove try-except, check 'validate' transition properly.
LIMS-2081: Remove try-except, check 'validate' transition properly.

labsanmartin/Bika-LIMS,labsanmartin/Bika-LIMS,veroc/Bika-LIMS,rockfruit/bika.lims,labsanmartin/Bika-LIMS,veroc/Bika-LIMS,veroc/Bika-LIMS,rockfruit/bika.lims