ProjectPart API fix
ProjectPart API fix

When a new ProjectPart is added, the Project link is automatically set
SchrodingersGat/InvenTree,inventree/InvenTree,SchrodingersGat/InvenTree,SchrodingersGat/InvenTree,inventree/InvenTree,SchrodingersGat/InvenTree,inventree/InvenTree,inventree/InvenTree