R1 Hotfix -> R2 Bugfix - Cannot approve multiline invoice with more than 15 linked encumbrances

Overview: Cannot approve multiline invoice with POLs connected to more than 15 invoice lines

Steps to Reproduce:

1. Log into bugfest-iris
2. Create Invoice
3. Create more than 15 invoice lines based on POLs
4. Click approve invoice

Expected Results: Invoice is successfully approved

Actual Results: Invoice is not approved. Generic error message is shown.

Additional Information: see example order in bugfest
I've set up two invoice examples in BugFest so far:
Invoice # 20210629 is approved with 15 POL linked invoice lines. https://bugfest-iris.folio.ebsco.com/invoice/view/c7783455-e698-461e-981a-04e4b7427f90?query=20210629
Invoice # 20210630 is not approved and generates the generic error message when I try to approve. It has 17 POL linked invoice lines. https://bugfest-iris.folio.ebsco.com/invoice/view/543ba9ff-1266-4dab-9e77-7505e9c6d2f0?query=20210630
One more example:
Invoice # 20210628 has 15 POL linked invoice lines and 3 not linked. It will not approve either. https://bugfest-iris.folio.ebsco.com/invoice/view/44758cd4-2783-4651-9edd-732c63d6487d?query=20210628

URL:
Interested parties: kpamplin