[ruby] Remove special handling of GraphQL response status code

[y9v]

Motivation

We are changing the way we are doing blocking for GraphQL in Ruby:
DataDog/dd-trace-rb#4300

https://datadoghq.atlassian.net/browse/APPSEC-56464

Changes

This PR removes special case for response status code assertion for Ruby when GraphQL response is being blocked.

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]

FYI, when only ruby is impacted, you can prefix with [ruby] (with square brackets), it'll run only ruby jobs.

side note, PHP failures are not related