Update cheatsheet.md

Adding a common command I use to ensure common or namespace wide ENV variables are properly set, i.e. by a ConfigMap

Author: robertsonai

content/en/docs/reference/kubectl/cheatsheet.md

@@ -216,6 +216,10 @@ kubectl get nodes -o json | jq -c 'path(..)|[.[]|tostring]|join(".")'
 
 # Produce a period-delimited tree of all keys returned for pods, etc
 kubectl get pods -o json | jq -c 'path(..)|[.[]|tostring]|join(".")'
+
+# Produce ENV for all pods
+# Make sure to set your default namespace or this will run on system pods
+for pod in $(kubectl get po --output=jsonpath={.items..metadata.name}); do echo $pod && kubectl exec -it $pod env; done
 ```
 
 ## Updating resources