feat: publish lib as Lambda Layer

[flochaz]

Description of your changes

• Integrate layer publication in CI/CD release process
• Publish doc on layer usage
• Add example on how to use it with CDK

How to verify this change

Release process: https://github.com/awslabs/aws-lambda-powertools-typescript/actions/runs/2826141922

A public version is already available under this ARN: arn:aws:lambda:{REGION}:094274105915:layer:AWSLambdaPowertoolsTypeScript:1 that was published during 1.0.2 release. So can be used in any deployment. An example of its usage is available in our CDK examples and be deploy simply:

cd examples/cdk
npm ci
npm run cdk deploy

Get to your AWS Console lambda , select the Lambda called MyLayeredFunction and check it's code and execution.

E2E tests has been added in the layer publisher as well.

Related issues, RFCs

#826

PR status

Is this ready for review?: NO
Is it a breaking change?: NO

Checklist

• Check tracking is in place for our layer
• Add doc in SAM README on how to set the layer
• Add doc on release process with manual update doc for version bump
• My changes meet the tenets criteria
• I have performed a self-review of my own code
• I have commented my code where necessary, particularly in areas that should be flagged with a TODO, or hard-to-understand areas
• I have made corresponding changes to the documentation
• I have made corresponding changes to the examples
• My changes generate no new warnings
• The code coverage hasn't decreased
• I have added tests that prove my change is effective and works
• New and existing unit tests pass locally and in Github Actions
• Any dependent changes have been merged and published in downstream module
• The PR title follows the conventional commit semantics

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By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

[dreamorosi]

Great work Florian, thank you fro this PR.

I've left only a couple of minor comments but it's already looking good.

[dreamorosi]

Is this s in External:s (<- this) on purpose? If yes please resolve this comment.

[flochaz]

oups , well catched

[flochaz]

Docker dependency might be an overkill, thinking about moving to a simple zip bundling:

mkdir nodejs && cd $_
npm init -y
npm install @aws-lambda-powertools/commons @aws-lambda-powertools/logger @aws-lambda-powertools/metrics @aws-lambda-powertools/tracer
rm package.json package-lock.json
cd ..
zip -r layer.zip nodejs

[ijemmy]

Suggested change

	This example bundle all your dependencies in a single JS file thanks to esbuild but you can switch the AWSLambdaPowertoolsTypeScript Layer by:
	This example bundles all your dependencies in a single JS file with `esbuild`. You can switch the `AWSLambdaPowertoolsTypeScript` Layer by:

[github-actions]

@awslabs/aws-lambda-powertools-typescript No related issues found. Please ensure 'pending-release' label is applied before releasing.