[Examples] Minor fixes

Author: peterschmidt85

docs/docs/guides/clusters.md

@@ -222,7 +222,6 @@ nav:
       - Guides:
           - Protips: docs/guides/protips.md
           - Metrics: docs/guides/metrics.md
-          - Clusters: docs/guides/clusters.md
           - Server deployment: docs/guides/server-deployment.md
           - Plugins: docs/guides/plugins.md
           - Troubleshooting: docs/guides/troubleshooting.md