Update dependency marked to v1.2.0

Author: renovate-bot

realworld/frontend/package-lock.json

@@ -8,7 +8,7 @@
   },
   "dependencies": {
     "history": "5.0.0",
-    "marked": "1.1.1",
+    "marked": "1.2.0",
     "prop-types": "15.7.2",
     "react": "16.13.1",
     "react-dom": "16.13.1",