[EZ] Metrics page bugfix (#6041)

Fixes a bug @clee2000 pointed out in
https://github.com/pytorch/test-infra/pull/6039/files#r1879220367 (that
PR got merged before I could push the fix)

torchci/pages/metrics.tsx

@@ -353,7 +353,7 @@ function WorkflowDuration({
 
   // -1 is the specical case where we will show the avg instead
   if (percentile === -1) {
-    title = `avg ${workflowNames.join(", ")} workflow duration`;
+    title = `avg ${workflowNames.join(", ")} TTS`;
     queryName = queryName.replace("percentile", "avg");
   }