feat: hoist `generateConfigFile` function

[zeucapua]

          nit: This is more or less duplicated in the `generateOutputFile` function. This could be an opportunity to hoist up that functionality into a `pkg/` function since we do alot of reading / writing yamls. Probably best for an additional PR / ticket since there's plenty to refactor in that suggestions.

Originally posted by @jpmcb in #207 (comment)