When marking an MO as done in the shop floor, the pre_mark_done method is used to determine if there are any issues before putting the MO in the 5 second validation queue. However, there were two cases that were not yet caught here: 1. Pending quality checks on a workorder 2. Duplicate serial number on the final product This commit adresses both of these cases. closes odoo/odoo#137535 Task: 3456827 (nr 28) Related: odoo/enterprise#48379 Signed-off-by: Steve Van Essche <svs@odoo.com>