feat(learn): add full stack certificate md and handle errors

Co-authored-by: Mrugesh Mohapatra <1884376+raisedadead@users.noreply.github.com>
Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com>

curriculum/challenges/_meta/full-stack-certificate/meta.json

@@ -0,0 +1,18 @@
+{
+  "name": "Full Stack Certificate",
+  "dashedName": "full-stack-certificate",
+  "order": 5,
+  "time": "",
+  "template": "",
+  "required": [],
+  "superBlock": "certificates",
+  "superOrder": 12,
+  "challengeOrder": [
+    [
+      "561add10cb82ac38a17213bd",
+      "Full Stack Certificate"
+    ]
+  ],
+  "isPrivate": true,
+  "fileName": "12-certificates/full-stack-certificate.json"
+}