We don't use product_id field anymore in contracts table. That column was used earlier when we were determining the product_tag information on the fly. We are not doing it anymore because we store that information in sku_product_tag table which we retrieve through sku in contracts table. 

This column creates confusion since we don't populate it anymore in table.

AC:

• Liquibase script to delete the column product_id column
• Update index if any present with product_id
• Testing will be regression