GP - Reduced checkbook transaction line number increment value (#28924)

This change enhances the GP to BC migration by fixing an issue seen when
a checkbook contains many transactions.
Fixes
[AB#592740](https://dynamicssmb2.visualstudio.com/1fcb79e7-ab07-432a-a3c6-6cf5a88ba4a5/_workitems/edit/592740)

Co-authored-by: jaymckinney <[email protected]>

Author: jaymckinney-enavate