Issue with insert/update/delete batching

I've found an issue when batching up insert, update and delete 
statements that occurs since version 4.2

I'm not sure if creating a ticket is enough or if I also should post it 
here, so just to make sure: https://issues.apache.org/jira/browse/CAY-2896

I've also created a PR that fixes the issue: 
https://github.com/apache/cayenne/pull/630

This currently blocks us from upgrading to a version without a CVE, 
since we're stuck at 4.1.1. Feel free to contact me, if anything is unclear.

Best regards

Chris