fixed a markdown error in the title

docs/user-guide/getting-into-containers.md

@@ -30,7 +30,9 @@ Documentation for other releases can be found at
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-#Getting into containers: kubectl exec
+
+# Getting into containers: kubectl exec
+
 Developers can use `kubectl exec` to run commands in a container. This guide demonstrates two use cases.
 
 ## Using kubectl exec to check the environment variables of a container