Outdated mappings, elastic beanstalk solution stacks

[hopkinsnji]

https://github.com/aws-samples/startup-kit-templates/blob/master/templates/elastic-beanstalk.cfn.yml#L128-L140

The mappings in this file are outdated. Run aws elasticbeanstalk list-available-solution-stacks > xxx.json to get the most recent solution stacks.