configs/configupgrade: Upgrade the bodies of "connection" blocks
configs/configupgrade: Upgrade the bodies of "connection" blocks

This uses the fixed "superset" schema from the main terraform package to
apply our standard expression mapping, with the exception of "type" where
interpolation sequences are not supported due to the type being evaluated
early to retrieve the schema for decoding the rest.

hashicorp/terraform-plugin-sdk,hashicorp/terraform-plugin-sdk