The restriction of product mix should apply during submission of another loan

For now when you configure one loan account of Product1 not to be applied when a client already have another loan account of Product2, during the application of another loan account, the system accept to submit and approve the loan and give the error of co-exist during disburse.

Expected: The system should give the error of co-exist of the restricted loan when a user is submitting the new loan account since the two loans should not exist together.