Global symbol "$banned_files_quarantine_to" requires explicit package name

[Damian]

> Tks a lot! It worked. Altough now I ask my self: how has this worked so
> far?

I do not know how it could have without noticing that it did not
quarantine via smtp. However, if your previous config file did not
include the strict pragma, it wouldn't have thrown an error.

> It says $banned_files_quarantine_method and *quarantine_to, implying it
> should be $banned_files_quarantine_to.

Yes, the variable names are inconsistent here.
You might have a look at [1] for another reference.

[1] https://gitlab.com/amavis/amavis/-/raw/master/amavisd.conf-default