How to deploy a serverless node app that requires private AWS resources?

I’m trying to deploy a nodejs serverless application that needs database access as part one of it’s core components. We have a private Aurora Postgre database that requires VPN access. You can’t deploy our serverless application if you are not connected to our VPN because the serverless application needs private access to our Aurora Postgre RDS instance. We are trying set a CI/CD pipeline for this, but we don’t want to expose our VPN to CircleCI.

Why does serverless try to connect to the private RDS instance while it’s building the artifact during deploy? Is that even necessary?

Does anyone have any recommendations? So far I have only been able to find this: