AWS Step Functions callback pattern sample in .NET

[umaskr]

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

To learn more about submitting a pattern, read the publishing guidelines page.

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).
• Framework: currently, we support SAM or CDK.
• 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.

GitHub PR for template: #1096

[uma075]

Created new PR for this #1131