feat(aws): set DD_SOURCE, DD_SERVICE, and DD_HOST for AWS Batch logs

[williamsbdev]

What does this PR do?

This PR sets the DD_SOURCE, DD_SERVICE, and DD_HOST values for logs coming from AWS Batch.

Motivation

All of our batch logs are lumped into one bucket. We'd like to be able to separate out our AWS Batch logs by job, using DD_SERVICE while having a simple value of batch for the DD_SOURCE. The DD_HOST is set to the use the Fargate container ID.

Testing Guidelines

Build this and update the forwarder lambda to use the new zip. Ensure that AWS Batch logs come through appropriately.

Types of changes

• Bug fix
• New feature
• Breaking change
• Misc (docs, refactoring, dependency upgrade, etc.)

Check all that apply

• This PR's description is comprehensive
• This PR contains breaking changes that are documented in the description
• This PR introduces new APIs or parameters that are documented and unlikely to change in the foreseeable future
• This PR impacts documentation, and it has been updated (or a ticket has been logged)
• This PR's changes are covered by the automated tests
• This PR collects user input/sensitive content into Datadog
• This PR passes the integration tests (ask a Datadog member to run the tests)
• This PR passes the unit tests
• This PR passes the installation tests (ask a Datadog member to run the tests)

[williamsbdev]

Checking in on this PR to see what else is needed.

I see @sabiurr and @jvanbrie have been the most recent contributors to new versions. Can you help coach/guide me on how best to submit a PR?

[williamsbdev]

@joaquinrios - I saw you approved a different PR. Can you help coach/guide me on how best to submit work for review?

[activehigh]

Hey guys, is this PR getting merged soon? We need this feature to include /aws/batch/job logs