Serverless RDS without a proxy example

[MushyMiddle]

Hi. lambda-function-connect-rds-iam seems to require an RDS Proxy. SDK v2 seems to have dropped support for non-proxy RDS. How does one use IAM authentication for RDS serverless without an RDS Proxy instance, which is very expensive? You can still do this via the CLI, and it was well-documented for SDK v1. E.g. see https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/UsingWithRDS.IAMDBAuth.Connecting.Java.html.