Sync eng/common directory with azure-sdk-tools for PR 8278 (#1589)

* Migrate stress cluster to use workload identity

* Only sleep to sync fed creds when namespace is new

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Co-authored-by: Ben Broderick Phillips <bebroder@microsoft.com>

eng/common/scripts/stress-testing/stress-test-deployment-lib.ps1

@@ -213,9 +213,17 @@ function DeployStressPackage(
     $imageTagBase += "/$($pkg.Namespace)/$($pkg.ReleaseName)"
 
     if (!$Template) {
-        Write-Host "Creating namespace $($pkg.Namespace) if it does not exist..."
-        kubectl create namespace $pkg.Namespace --dry-run=client -o yaml | kubectl apply -f -
-        if ($LASTEXITCODE) {exit $LASTEXITCODE}
+        Write-Host "Checking for namespace $($pkg.Namespace)"
+        kubectl get namespace $pkg.Namespace
+        if ($LASTEXITCODE) {
+            Write-Host "Creating namespace $($pkg.Namespace) ..."
+            kubectl create namespace $pkg.Namespace --dry-run=client -o yaml | kubectl apply -f -
+            if ($LASTEXITCODE) {exit $LASTEXITCODE}
+            # Give a few seconds for stress watcher to initialize the federated identity credential
+            # and create the service account before we reference it
+            Write-Host "Waiting 15 seconds for namespace federated credentials to be created and synced"
+            Start-Sleep 15
+        }
         Write-Host "Adding default resource requests to namespace/$($pkg.Namespace)"
         $limitRangeSpec | kubectl apply -n $pkg.Namespace -f -
         if ($LASTEXITCODE) {exit $LASTEXITCODE}