release: do not require a rebuild on configuration changes

Created by: bobheadxi

This has been a big source of gotcha mistakes for me, where I forget to rebuild the release tool after updating a configuration value.

A rebuild must happen at the moment because we import the config file directly - instead, we should probably just read it in at runtime. This will allow us to use a more informative format such as JSONC for configuration as the number of options grows.