docs: corrected a typo in last-updated plugin docs (#2423)

Simon Kunz · web-flow · commit 017aa6928929 · 2020-06-09T20:42:18.000+08:00
diff --git a/packages/docs/docs/plugin/official/plugin-last-updated.md b/packages/docs/docs/plugin/official/plugin-last-updated.md
@@ -71,7 +71,7 @@ module.exports = {
       '@vuepress/last-updated',
       {
         dateOptions:{
-          hours12: false
+          hour12: false
         }
       }
     ]
