looks like an old post but but making it more detailed because I myself faced it and made me searching multiple posts for actual steps.
First of all, you don't need to create a new binary because you just forgot to select In App purchases for review. Below are the steps how you can do this
Before making the Application "Ready to Upload" you need to select all the In App Purchases in Applicatin's Detail Page.
At iTunes Connect -> Click your application -> Click Edit -> scroll to bottom, you would see In App Purchase link, select the In Apps you want to make the part of your Application Submission Process. Once you are confirmed then change your product status to "Ready to Upload Binary"
If somehow you forgot to do that then there is only 1 way. Which is Reject and then Re Do the process I mentioned above.
