Maintenance: update layer update script to bump GovCloud ARN

[dreamorosi]

Summary

As per title, we should update this script that is run after each release so that it bumps the Layer version for GovCloud layers in the docs.

Why is this needed?

So that customers can have the correct ARN in the docs, and we don't have to bump it manually.

Which area does this relate to?

Automation

Solution

No response

Acknowledgment

• This request meets Powertools for AWS Lambda (TypeScript) Tenets
• Should this be considered in other Powertools for AWS Lambda languages? i.e. Python, Java, and .NET

Future readers

Please react with 👍 and your use case to help us understand customer demand.

[dreamorosi]

While working on this, we should also make sure the script updates the ARN in the correct file, which is now docs/getting-started/lambda-layers.md.