Load environment variables from SecretsManager

### Community Note

* Please vote on this issue by adding a 👍 [reaction](https://blog.github.com/2016-03-10-add-reactions-to-pull-requests-issues-and-comments/) to the original issue to help the community and maintainers prioritize this request
* Please do not leave "+1" or "me too" comments, they generate extra noise for issue followers and do not help prioritize the request
* If you are interested in working on this issue or have submitted a pull request, please leave a comment

**Tell us about your request**
I would love if Lambda support loading values for environment variables from SecrtesManager like ECS does. This would prevent varaibles to be visible in the Lambda console but still make them easily usable inside my function code.

**Which service(s) is this request for?**
AWS Lambda, Secretsmanager

**Tell us about the problem you're trying to solve. What are you trying to do, and why is it hard?**
see above

**Are you currently working around this issue?**
Currently, I can use environment encryption to partly solve that.

**Additional context**
N/A

**Attachments**
N/A

Es werden keine Dateien, Tests oder Einstiegspunkte erwähnt. Beginne damit, das erforderliche Integrationsverhalten von AWS Lambda und Secrets Manager zu klären, einschließlich der Berechtigungen und der Frage, wie Werte dem Funktionscode bereitgestellt werden sollen, während sie in der Lambda-Konsole verborgen bleiben; abgeschlossen ist die Aufgabe, wenn dieses End-to-End-Verhalten spezifiziert und unterstützt wird.

Vom Indexierungsmodell aus dem Issue-Text verfasst.