Update dojo-e2e.yml

Setup Workload Identity Federation

(cherry picked from commit 979b3dc)

Author: contextablemark

.github/workflows/dojo-e2e.yml

@@ -153,6 +153,13 @@ jobs:
         echo "LANGSMITH_API_KEY=${LANGSMITH_API_KEY}" >> examples/typescript/.env
         echo "OPENAI_API_KEY=${OPENAI_API_KEY}" > python/ag_ui_langgraph/.env
         echo "LANGSMITH_API_KEY=${LANGSMITH_API_KEY}" >> python/ag_ui_langgraph/.env
+        
+    - name: setup workload identity federation
+      uses: 'google-github-actions/auth@v3'
+      with:
+        service_account: 'vertex-express@contextable-ci-builds-474115.iam.gserviceaccount.com'
+        workload_identity_provider: 'projects/27343391129/locations/global/workloadIdentityPools/github/providers/my-repo' 
+
 
     - name: Run dojo+agents
       uses: JarvusInnovations/background-action@v1