Enable OpenTelemetry tests for Ruby

[marcotc]

Description

This PR implements the parametric system-tests gRPC server to back the Ruby Tracer OpenTelmetry integration.

All tests are passing for Ruby after this PR merges.

Depends on DataDog/dd-trace-rb#3026 to be released for tests to go green.

Motivation

Workflow

1. ⚠️⚠️ Create your PR as draft
2. Follow the style guidelines of this project (See how to easily lint the code)
3. Work on you PR until the CI passes (if something not related to your task is failing, you can ignore it)
4. Mark it as ready for review

Once your PR is reviewed, you can merge it! ❤️

Reviewer checklist

• Check what scenarios are modified. If needed, add the relevant label (run-parametric-scenario, run-profiling-scenario...). If this PR modifies any system-tests internal, then add the run-all-scenarios label (more info).
• CI is green
  • If not, failing jobs are not related to this change (and you are 100% sure about this statement)
• if any of build-some-image label is present
  1. is the image labl have been updated ?
  2. just before merging, locally build and push the image to hub.docker.com
     When we hit the rate limit (HTTP 429), retry after the time specified in
     the response. This does not count toward the number of retries based on
     other criteria.

[cbeauchesne]

ruby fails in CI/parametric, is it related ?

Tests are fixed

[cbeauchesne]

Hi @marcotc , it's still failing on activated test, or did I missed something ?

https://github.com/DataDog/system-tests/actions/runs/6937541248/job/18871827685?pr=1456#step:4:1024

Fixed the issues pointed out, thank you!