Use Green deployment descriptor for creating blue stack

[mbloch1986]

The AEM AWS Stack Builder allows it to use the deployment descriptor of the green stack to create the blue AEM Stack

https://github.com/shinesolutions/aem-aws-stack-builder/blob/master/provisioners/ansible/playbooks/apps/aem/stack-data.yaml#L101-L109

However the blue/green pipeline only use the source stack prefix atm to generate a configuration file for using the correct snapshot ids. We need to improve this process to also generate a configuration file which allows it to use the deployment descriptor of the green stack.