[formrecognizer] fix broken link (Azure#18921)

This seems to have been updated overnight

Author: kristapratico

sdk/formrecognizer/azure-ai-formrecognizer/README.md

@@ -482,7 +482,7 @@ This project has adopted the [Microsoft Open Source Code of Conduct][code_of_con
 [azure_portal_create_FR_resource]: https://ms.portal.azure.com/#create/Microsoft.CognitiveServicesFormRecognizer
 [azure_cli_create_FR_resource]: https://docs.microsoft.com/azure/cognitive-services/cognitive-services-apis-create-account-cli?tabs=windows
 [azure-key-credential]: https://aka.ms/azsdk/python/core/azurekeycredential
-[fr-labeling-tool]: https://docs.microsoft.com/azure/cognitive-services/form-recognizer/quickstarts/label-tool
+[fr-labeling-tool]: https://docs.microsoft.com/azure/cognitive-services/form-recognizer/label-tool?tabs=v2-1
 [fr-train-without-labels]: https://docs.microsoft.com/azure/cognitive-services/form-recognizer/overview#train-without-labels
 [fr-train-with-labels]: https://docs.microsoft.com/azure/cognitive-services/form-recognizer/overview#train-with-labels
 [prefix_ref_docs]: https://aka.ms/azsdk/python/formrecognizer/docs#azure.ai.formrecognizer.FormTrainingClient.begin_training