fix Contributor License Agreement broken link

Author: mahmud2011

CONTRIBUTING.md

@@ -6,6 +6,6 @@ The [Kubernetes community repo](https://github.com/kubernetes/community) contain
 
 ## Sign the CLA
 
-You must sign the [Contributor License Agreement](https://git.k8s.io/community/contributors/guide/getting-started.md#sign-the-cla) in order to contribute.
+You must sign the [Contributor License Agreement](https://git.k8s.io/community/contributors/guide/README.md#sign-the-cla) in order to contribute.
 
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