Update container referenced in README

Author: gkrizek

README.md

@@ -152,7 +152,7 @@ To publish the layer to the public, simply run `make publish`. This will create
 
 Some executables are able to run by themselves and some require additional dependencies that are present on the server. It's hard to cover here case here, but if the executable run by itself it can easily be added. If it has dependencies, you must explore what those dependencies are and how to add them to the layer as well.
 
-You can either add the executable from an Amazon Linux AMI or from the [lambci/lambda-build:python-36](https://github.com/lambci/docker-lambda) Docker image.
+You can either add the executable from an Amazon Linux AMI or from the [lambci/lambda:build-python3.6](https://github.com/lambci/docker-lambda) Docker image.
 
 _Disclaimer: I usually don't add in executables from pull requests for security reasons. If you would like to see an executable in this layer make an issue and I'll try to add it._