Add architecture validations for SAM build LambdaLayer

[bentvelj]

• Add a validation check for LambdaLayer BuildArchitecture to ensure that it is a valid architecture and one of the CompatibleArchitectures listed. If the BuildArchitecture is invalid, only a warning is displayed to inform the customer. Hard failing is not done for Makefile BuildMethod to preserve customer freedom in building with their own Makefile.

• Adds architecture validation for when --use-container is specified for building a LambdaLayer. This now gives the customer a much clearer error message regarding the architecture instead of a "failed to pull image" error. (@mndeveci's changes)

• Adds integration test to verify that a clear error message is displayed in the case of a customer attempting to build a function with an invalid architecture.

Which issue(s) does this change fix?

#6110

Why is this change necessary?

• Customers may be confused why LambdaLayers with invalid BuildArchitectures still build just fine. A warning message will help customers catch possible errors in their template.

• Regarding the --use-container option for building a layer, reporting an invalid architecture error addresses the actual root of the problem instead of showing a consequence of having an invalid architecture ("failed to pull image" error). This makes it easier for customers to resolve.

How does it address the issue?

• Add warning message if the LambdaLayer being built has a BuildMethod of Makefile. Architecture validation for other BuildMethods are already done in LambdaBuilders, but nothing is done for Makefile.

What side effects does this change have?

N/A

Mandatory Checklist

PRs will only be reviewed after checklist is complete

• Add input/output type hints to new functions/methods
• Write design document if needed (Do I need to write a design document?)
• Write/update unit tests
• Write/update integration tests
• Write/update functional tests if needed
• make pr passes
• make update-reproducible-reqs if dependencies were changed
• Write documentation

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

[mildaniel]

Thanks Jared, LGTM overall. Left a few minor comments.

Let's also write some unit tests for the changes in lib/build to ensure we don't lose coverage there.

[sidhujus]

LGTM