When using the v2 global setup script I came across a method that had leaked some of its state. Specifically dbName. Talking to @QuentinAmbard about it, that was being pulled from scope elsewhere outside of here. The change is to simply use db instead of dbName

Error origination: https://github.com/databricks-demos/dbdemos-notebooks/blob/main/_resources/00-global-setup-v2.py#L44

I can create a PR specifically for this issue, so we don't potentially introduce regressions from my unrelated CDC code.