update error mapping to catch when Lambda layer ARN regions do not match function region

Problem

Work done in https://github.com/aws-amplify/amplify-backend/pull/2188 was too eager (no solid way to validate layer arn region with function region during synthesis). Reverting this change leaves us with the original error when layer arn region is not the same as function region which is not great:

The CloudFormation deployment has failed.
Caused By: The stack named <stack> failed to deploy: UPDATE_ROLLBACK_COMPLETE: Resource handler returned message: "User: <user-arn> is not authorized to perform: lambda:GetLayerVersion on resource: <layer-arn> because no resource-based policy allows the lambda:GetLayerVersion action...

Resolution: Find more information in the CloudFormation AWS Console for this stack.

Issue number, if available:

Changes

Update error mapping with instructions to check Lambda layer ARNs and make sure regions are correct. New error message:

Unable to get layer version
Caused By: User: <user-arn> is not authorized to perform: lambda:GetLayerVersion on resource: <layer-arn> because no resource-based policy allows the lambda:GetLayerVersion action

Resolution: Make sure layer ARNs are correct and regions match function region

Corresponding docs PR, if applicable:

Validation

Unit tests.

Checklist

[ ] If this PR includes a functional change to the runtime behavior of the code, I have added or updated automated test coverage for this change.
[ ] If this PR requires a change to the Project Architecture README, I have included that update in this PR.
[ ] If this PR requires a docs update, I have linked to that docs PR above.
[ ] If this PR modifies E2E tests, makes changes to resource provisioning, or makes SDK calls, I have run the PR checks with the run-e2e label set.

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

aws-amplify / amplify-backend