feat(receiver): aws-like report log for invocations

[adamantal]

Description

AWS Lambda users can see the following report in AWS Cloudwatch after the invocation has finished:

REPORT RequestId: bf5f58db-ef7d-4cb2-b3c6-266eba1bbedb Duration: 395.99 ms Billed Duration: 662 ms Memory Size: 512 MB Max Memory Used: 301 MB Init Duration: 265.72 ms

This pull request adds the ability to display these report and send them along with the regular Lambda application logs. This feature is hidden behind a flag (log_report), which is turned off by default.

Contrary to what someone could expect based on the documentation, these metrics are all floats, attempt to parse them as integers would fail.

Testing

Added unit test coverage, and tested in a production environment.
Attaching a Grafana log query for evidence (we're using Otel -> Alloy -> Loki -> Grafana pipeline)

Collector config extract:

receivers:
  telemetryapi:
    types: [platform, function]
    log_report: true

extensions:
  basicauth/otlp:
    ...

exporters:
  otlphttp:
    auth:
      authenticator: basicauth/otlp
    endpoint: ...

processors:
  batch: {}
  decouple: {}

service:
  pipelines:
    logs:
      receivers: [telemetryapi]
      processors: [batch, decouple]
      exporters: [otlphttp]
  extensions: [basicauth/otlp]