SLS-2070: Adds step function forwarding to forwarder

[IvanTopolcic]

What does this PR do?

This PR adds step function forwarding. A related logs-backend PR for logs processing has been created here.

Motivation

Adds step function log forwarding for our customers.

Testing Guidelines

Tested manually in sandbox, and has unit tests.

Additional Notes

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)

[IvanTopolcic]

I'll go ahead and merge these changes next week when the logs configuration pipelines are deployed to production.