Bootstrap option does not take chef_config_dir into account

[almog]

Regardless of the chef_config_dir value, Gusteau::Chef#run uses the default config dir.

While I already patched it, I couldn't think of a good way to test it, the chef_spec.rb isn't the right place even though it is possible to test it there.
Where do you think is the right place to test/fix it?

Thanks for spotting this. I would test it in chef_spec.rb.