bin/config_build.py non-functional

[pleia2]

We have a configuration builder at bin/config_build.py that was historically used to auto-generate a custom supported_distros.py rather than relying upon manual edits.

This script is supposed to scour the distro_data/data_files/ directory and generate the file based on what it finds there, but it's not functional at the moment.

We need to:

1. Determine whether we want to keep this script
2. If so, figure out how to fix it