chore: update CODEOWNERS

[danielvnguyen]

What this PR does

Removes past team members from the CODEOWNERS file

Why we need it

Checklist

• I followed the contributing guide
• [] I added or updated the documentation (if applicable)
• [] I updated docs/changelog.md with user-relevant changes
• [] I added a change artifact for user-relevant changes in docs/release-notes/artifacts. If no change artifact is necessary, I tagged the PR with the label no-release-note.
• I added or updated tests as needed (unit and integration)
• If integration test modules are used: I updated the workflow configuration
  (e.g., in .github/workflows/integration_tests.yaml, ensure the modules list is correct)
• If this is a Grafana dashboard: I added a screenshot of the dashboard
• If this is Terraform: terraform fmt passes and tflint reports no errors
• If this is Rockcraft: I updated the version