New pattern submission: Step Function to durable Lambda function

To submit a template to the Serverless Patterns Collection, submit an issue with the following information.

**IMPORTANT**
Patterns are intended to be primarily IaC-focused implementations of 2-4 AWS services, with minimum custom code. They should be commonly used combinations that help developers get started quickly. If you have a utility, demo, or application, submit these to the [Serverless Repos Collection](https://serverlessland.com/repos) instead.

**ONLY SUBMIT ONE PATTERN CHANGE PER PR**. Multiple patterns or files spanning multiple pattern directories will be automatically rejected.

Patterns may take up to 4-6 weeks to review, test, and merge but there is no SLA and can take significantly longer due to other work the team has.

**To learn more about submitting a pattern, read the [publishing guidelines page](https://github.com/aws-samples/serverless-patterns/blob/main/PUBLISHING.md).**

1. Use the model template located at https://github.com/aws-samples/serverless-patterns/tree/main/_pattern-model to set up a README, template and any associated code.

2. THIS PROCESS HAS BEEN SIMPLIFIED. All the information below must be provided in the "example-pattern.json" file cloned from the model **

Note the following information for the model:
- Description (intro.text) should be a 300-500 word explanation of how the pattern works.
- Resources should like to AWS documentation and AWS blogs related to the post (1-5 maximum).
- Author bio may include a LinkedIn and/or Twitter reference and a 1-sentence bio.

You must ensure that the sections of the model README.md are completed in full.

All required details filled in the `serverless-patterns/cdk-stepfunction-durable-lambda-function/stepfunction-durablelambdafunction-pattern.json` file.

## GitHub PR for template: #2975

Lies PUBLISHING.md und _pattern-model, untersuche anschließend die genannte Datei cdk-stepfunction-durable-lambda-function/stepfunction-durablelambdafunction-pattern.json sowie PR #2975. Fertig ist die Aufgabe, wenn die README des Modells, das Template, der zugehörige Code und die erforderlichen Pattern-Details vollständig und bereit für das Review sind.

Vom Indexierungsmodell aus dem Issue-Text verfasst.