Context not propagated for autoinstrumented lambda

[cleverchuk]

Describe the bug

When a Lambda that's triggered by API Gateway is auto-instrumented, context is not propagated.

Steps to reproduce

• Create a Lambda with API Gateway as trigger
• Auto-instrument with Java agent Lambda layer
• Use a HTTP client from an instrumented service to make a http request to the Lambda's API Gateway endpoint

Expected behavior

A trace with both service and Lambda spans.

Actual behavior

Two traces one for the service and one for the lambda

Javaagent or library instrumentation version

2.8.0

Environment

JDK: 17
OS: Linux

Additional context

This line seems to be the issue because it doesn't extract context and uses empty map instead.

[cleverchuk]

@tylerbenson

[cleverchuk]

please assign to me

[laurit]

Resolved with #12440