[skipci] Set alwaysApply: false for SSI rules

[bm1549]

Motivation

Saves a bit more of the context window

Changes

Disable alwaysApply for SSI-related rules

Workflow

1. ⚠️ Create your PR as draft ⚠️
2. Work on you PR until the CI passes
3. Mark it as ready for review
   • Test logic is modified? -> Get a review from RFC owner.
   • Framework is modified, or non obvious usage of it -> get a review from R&P team

🚀 Once your PR is reviewed and the CI green, you can merge it!

🛟 #apm-shared-testing 🛟

Reviewer checklist

• Anything but tests/ or manifests/ is modified ? I have the approval from R&P team
• A docker base image is modified?
  • the relevant build-XXX-image label is present
• A scenario is added, removed or renamed?
  • Get a review from R&P team

[github-actions]

CODEOWNERS have been resolved as:

.cursor/rules/aws-ssi-testing.mdc                                       @DataDog/system-tests-core
.cursor/rules/k8s-ssi.mdc                                               @DataDog/system-tests-core