fix(kubectx): show plain context if not mapped (#10134)

plugins/kubectx/kubectx.plugin.zsh

@@ -3,12 +3,7 @@ typeset -A kubectx_mapping
 function kubectx_prompt_info() {
   if [ $commands[kubectl] ]; then
     local current_ctx=`kubectl config current-context`
-
-    #if associative array declared
-    if [[ -n $kubectx_mapping ]]; then
-      echo "${kubectx_mapping[$current_ctx]}"
-    else
-      echo $current_ctx
-    fi
+    # use value in associative array if it exists, otherwise fall back to the context name
+    echo "${kubectx_mapping[$current_ctx]:-$current_ctx}"
   fi
 }