enable trace sampling tests for Ruby

[ZStriker19]

Motivation

When this PR merges Ruby tracer master branch will pass all of the trace sampling tests (tested this locally)
DataDog/dd-trace-rb#3956

Changes

Enable lazy sampling/ tag and resource sampling tests for Ruby tracer.

Workflow

1. ⚠️ Create your PR as draft ⚠️
2. Work on you PR until the CI passes (if something not related to your task is failing, you can ignore it)
3. Mark it as ready for review
   • Test logic is modified? -> Get a review from RFC owner. We're working on refining the codeowners file quickly.
   • Framework is modified, or non obvious usage of it -> get a review from R&P team

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

🛟 #apm-shared-testing 🛟

Reviewer checklist

• If PR title starts with [<language>], double-check that only <language> is impacted by the change
• No system-tests internal is modified. Otherwise, I have the approval from R&P team
• CI is green, or failing jobs are not related to this change (and you are 100% sure about this statement)
• A docker base image is modified?
  • the relevant build-XXX-image label is present
• A scenario is added (or removed)?
  • Get a review from R&P team

[cbeauchesne]

Small hint for future PR : when your change only impacts ruby, you can prefix your PR title with [ruby] -> it will run only ruby in the CI.

In theory, it's automatic when you modify only a manifest files. But the current logic failed to understand that the modif on the doc file has no impact, and thus ran all langs 🤦 .