Part of staging account setup fixes.
This diff resolves an issue when running terraform plan on plain fresh AWS account. The `aws_dynamodb_table` data doesn't resolve to anything because the DDB table isn't yet created.
Resources from inside module aren't globally exposed, so I created a `outputs.tf` file in the shared module and iterated over explicitly-specified table resources to expose them.
> I really wanted to do it in a more automated way, but TF has no good mechanism for iterating over all resources yet. There's an [[ https://github.com/hashicorp/terraform/issues/19931 | open issue ]] for that where people share other usecases for such feature.
Depends on D8714