fix: easy win activation (#6941)

Author: nccatoni

.github/chainguard/self.test-activation-github.sts.yaml

@@ -3,7 +3,7 @@ issuer: https://token.actions.githubusercontent.com
 
 subject: repo:DataDog/system-tests:ref:refs/heads/main
 claim_pattern:
-  event_name: (workflow_dispatch|schedule)
+  event_name: (workflow_dispatch|schedule|push)
   ref: refs/heads/main
   ref_protected: "true"
   job_workflow_ref: DataDog/system-tests/\.github/workflows/nightly\.yml@refs/heads/main

.github/workflows/nightly.yml

@@ -205,7 +205,7 @@ jobs:
         if: steps.activation_script.outputs.activation_exit_code == '0' && steps.activation_script.outputs.branches != ''
         with:
           repository: DataDog/commit-headless
-          ref: action/v2.0.3
+          ref: action/v3.3.0
           path: .commit-headless
 
       - name: Push signed branches and create PRs