corrected path in AWS config

Summary:
WEB-208 #fixed
corrected path in AWS config

Test Plan: once on develop change stage stack to use the develop branch of the cookbooks. run update cookbooks, and then deploy. Make sure the deploy succeeds and that emails still work on stage.

Reviewers: #everyone, gwarner

Reviewed By: #everyone, gwarner

Subscribers: gwarner

Differential Revision: https://dev.blendtec.com/D1489