fix access denied error for accessing merch sales

Author: devksingh4

cloudformation/iam.yml

@@ -100,6 +100,7 @@ Resources:
             Resource:
               - Fn::Sub: arn:aws:dynamodb:${AWS::Region}:${AWS::AccountId}:table/infra-core-api-stripe-links/index/*
               - Fn::Sub: arn:aws:dynamodb:${AWS::Region}:${AWS::AccountId}:table/infra-core-api-events/index/*
+              - Fn::Sub: arn:aws:dynamodb:${AWS::Region}:${AWS::AccountId}:table/infra-merchstore-purchase-history/index/*
 
           - Sid: DynamoDBStreamAccess
             Effect: Allow