Merge pull request #30639 from czahedi/patch-1

Automatic merge from submit-queue

Updated Google Groups link

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**What this PR does / why we need it**: This is a small change to the markdown on a Troubleshooting document redirecting from a deprecated Google group to the accurate, active group. 

**Special notes for your reviewer**:

**Release note**:

```NONE
```

What was google-containers@googlegroups.com is now kubernetes-users@googlegroups.com. Links were updated in the troubleshooting document.

docs/troubleshooting.md

@@ -69,7 +69,7 @@ The Kubernetes team hangs out on Slack in the `#kubernetes-users` channel.  You
 
 ## Mailing List
 
-The Google Container Engine mailing list is [google-containers@googlegroups.com](https://groups.google.com/forum/#!forum/google-containers)
+The Google Container Engine mailing list is [kubernetes-users@googlegroups.com](https://groups.google.com/forum/#!forum/kubernetes-users)
 
 ## Bugs and Feature requests