chore(ci): use dd-sts for system-tests test optimization

Author: nccatoni

.github/workflows/system-tests.yml

@@ -60,3 +60,4 @@ jobs:
       parametric_job_count: 8
       skip_empty_scenarios: true
       push_to_test_optimization: ${{ github.actor != 'dependabot[bot]' }}
+      dd_sts_policy: httpd-datadog