fix contributor

Author: komaksym

questions/188_gradient-checkpointing/meta.json

@@ -6,5 +6,10 @@
   "video": "",
   "likes": "0",
   "dislikes": "0",
-  "contributor": ["https://github.com/komaksym"]
+  "contributor": [
+      {
+        "profile_link": "https://github.com/komaksym",
+        "name": "komaksym"
+      }
+    ]
 }