How to debug In-place upgrade of the engine to the new target version 8.0.mysql_aurora.3.01.0 is not supported.

In-place upgrades to Aurora 3 are currently not supported.

In order to upgrade your Aurora 2 MySQL cluster i.e. MySQL 5.7 to Aurora 3 MySQL cluster i.e. MySQL 8, you will need to create a snapshot of your Aurora 2 cluster and restore it as Aurora 3.

[+] https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/AuroraMySQL.Updates.MajorVersionUpgrade.html#AuroraMySQL.Upgrading.Sequence