Fix broken links in docs. (#9148)

Author: ryanyuan

packages/google-cloud-runtimeconfig/README.rst

@@ -35,7 +35,7 @@ In order to use this library, you first need to go through the following steps:
 
 .. _Select or create a Cloud Platform project.: https://console.cloud.google.com/project
 .. _Enable billing for your project.: https://cloud.google.com/billing/docs/how-to/modify-project#enable_billing_for_a_project
-.. _Enable the Google Cloud RuntimeConfig API.:  https://cloud.google.com/runtimeconfig
+.. _Enable the Google Cloud RuntimeConfig API.:  https://cloud.google.com/deployment-manager/
 .. _Setup Authentication.: https://googleapis.dev/python/google-api-core/latest/auth.html
 
 Installation