Having auto_minor_version_upgrade enabled on RDS DB instance causes Terraform to break

[briferz]

Hello everyone.

I have found out that having the auto_minor_version_upgrade attribute being omitted (which defaults to true) on this resource while also having this engine version causes AWS to automatically upgrade Postgres to a newer version (in my case 13.10) and Terraform Apply to fail since it's unable to downgrade the DB instance.