devel/py-aws-sam-translator: Update to 1.15.1

Changelog since 1.14.0:

https://github.com/awslabs/serverless-application-model/releases/tag/v1.15.0
https://github.com/awslabs/serverless-application-model/releases/tag/v1.15.1

PR: 241454
Submitted by: nork@ninth-nine.com (maintainer)