feat(cmd): Add S3-SQS Handler

[jshlbrd]

Description

• Adds an S3 -> SQS handler to the AWS Lambda application.
• Refactors all S3 handlers to use the same ingest function.

Motivation and Context

The AWS Lambda app was missing support for S3 notifications sent over SQS. There's some complexity with this architecture because SQS can also encapsulate SNS, but this change covers both uses under the AWS_S3_SQS handler.

How Has This Been Tested?

This was tested in a production AWS account using an SNS encapsulated SQS queue.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.

[jtan-brex]

@jshlbrd Thanks for incorporating this! Changes looked good 👍 Had one question about error handling method.