Validate all IAST endpoints

[smola]

Motivation

Validate that the response status code for all IAST test is 200. This helps detecting missing endpoints, as well as avoiding passing tests with endpoints that are incorrectly implemented or bugged.

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

:rocket: 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