E2E Testing: Create release testing workflow

[majanjua-amzn]

Run E2E test on demand for when changes are made to the enablement script.

Changes:

• Create new release testing workflow
• Create E2E test workflow for EKS as in ADOT repo
  • Changes made to this to pull the testing resources directly from ADOT (by pulling ADOT repo altogether)
  • Removed steps specific to ADOT (removed release testing check for ADOT, removed failure metric emission)
  • Calling API ahead of validation as an improvement (same change is planned for ADOT repo)

Note: This workflow does not test on PR because the AWS credential configuration using OIDC does not work under the context of a PR build (permissions are automatically set to read instead of write for id-token) - example of the operation hanging

Testing:
https://github.com/aws-observability/application-signals-demo/actions/runs/7135333263

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[harrryr]

LGTM