Fix building unknown smoke test configs

Author: mullermp

build_tools/aws-sdk-code-generator/lib/aws-sdk-code-generator/views/features/smoke.rb

@@ -104,7 +104,7 @@ def config_map(raw_key, raw_value)
             when 'useAccountIdRouting' then nil # TODO
             else
               # catch all, possible code generated config options
-              [downcase(raw_key), raw_value]
+              [underscore(raw_key), raw_value]
             end
           end