re-enable Prod tests (Azure#22174)

Author: catalinaperalta

sdk/formrecognizer/tests.yml

@@ -13,9 +13,9 @@ stages:
       # their claim is that the full matrix ends up stress-testing their service.
       # As such, the canary test runs should run on a reduced matrix.
       CloudConfig:
-#         Prod:
-#           SubscriptionConfiguration: $(sub-config-azure-cloud-test-resources)
-#           Location: $(LOCATION)
+        Prod:
+          SubscriptionConfiguration: $(sub-config-azure-cloud-test-resources)
+          Location: $(LOCATION)
         Canary:
           SubscriptionConfiguration: $(sub-config-azure-cloud-test-resources)
           Location: 'centraluseuap'