WebsiteDeployHelper Lambda uses unsupported python runtime version

Describe the bug In the nested stack "EFSFileWebApplication" the WebsiteDeployHelper can not be created because it tries to use a no longer supported runtime version for lambda.

Full error:

2022-08-18 12:15:36 UTC+0200	WebsiteDeployHelper	CREATE_FAILED	Resource handler returned message: "The runtime parameter of python3.6 is no longer supported for creating or updating AWS Lambda functions. We recommend you use the new runtime (python3.9) while creating or updating functions. (Service: Lambda, Status Code: 400, Request ID: dadadadada)" (RequestToken: dadadadadadada, HandlerErrorCode: InvalidRequest)

To Reproduce Deploy the stack with CloudFormation

Expected behavior It runs through without errors

Version: (SO0145) Simple File Manager for Amazon EFS Solution Main v1.4.0

Mappings:
  SourceCode:
    General:
      S3Bucket: "solutions"
      KeyPrefix: "simple-file-manager-for-amazon-efs/v1.0.4"

[ ] Region: [e.g. eu-central-1]
[ ] Was the solution modified from the version published on this repository? NO
[ ] If the answer to the previous question was yes, are the changes available on GitHub?
[ ] Have you checked your service quotas for the sevices this solution uses? NO
[ ] Were there any errors in the CloudWatch Logs?

aws-solutions / simple-file-manager-for-amazon-efs

WebsiteDeployHelper Lambda uses unsupported python runtime version #171