s2n's config wasn't getting passed into the Project constructor correctly (#141)

Author: bretambrose

builder/imports/s2n.py

@@ -30,6 +30,6 @@ def __init__(self, **kwargs):
         super().__init__(
             account='awslabs',
             imports=['aws-lc'],
-            config=config,
             url='https://github.com/aws/s2n-tls.git',
+            **config,
             **kwargs)