Added product preparation model to models.py
Added product preparation model to models.py

refs #16581

osu-cass/whats-fresh-api,iCHAIT/whats-fresh-api,iCHAIT/whats-fresh-api,osu-cass/whats-fresh-api,iCHAIT/whats-fresh-api,iCHAIT/whats-fresh-api,osu-cass/whats-fresh-api,osu-cass/whats-fresh-api